OWASP Secure Headers Project

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OWASP Secure Headers Project The OWASP Secure Headers Project describes HTTP response headers that your application can use to increase the security of your application. Once set, these HTTP response headers can restrict modern browsers from running into easily preventable vulnerabilities. The OWASP Secure Headers Project intends to raise awareness and use of these headers. Introduction HTTP headers are well known and also despised. Seeking the balance between usability and security developers implement functionality through the headers that can make your more versatile or secure application. But in practice how the headers are being implemented? What sites follow the best implementation practices? Big companies, small, all or none? Description We aim to publish reports on header usage stats, developments and changes. Code libraries that make these headers easily accessible to developers on a range of platforms. Data sets concerning the general usage of these headers. Licensing OWASP Secure Headers is free to use. It is licensed under the Apache 2.0 License.

Project Leader Ricardo Iramar Alexandre Menezes Project Contributors Jim Manico Related Projects OWASP Application Security Verification Standard Project OWASP Top Ten Project Quick Links Project GitHub Organization Docker Hub Organization Demo [develop preview] hsecscan A security scanner for HTTP response headers Project Email List

News and Events [23 Jul 2018] Included Feature-Policy header [20 Oct 2017] OWASP Secure Headers Project on | OWASP Top 10 RC2 [14 Mar 2017] | Docker Hub Organization [15 Oct 2016] | RoadSec Curitiba 2016 Presentation [20/21 Set 2016] | Mind The Sec 2016 Presentation [05 Sep 2016] | Project Github Organization [01 Sep 2016] Included X-Permitted-Cross-Domain-Policies header [14 Dec 2015] Reborn from the ashes Classifications

The following contains a list of HTTP response headers related to security.

Response Headers

• HTTP Strict Transport Security (HSTS)
• Public Key Pinning Extension for HTTP (HPKP)
• X-Frame-Options
• X-XSS-Protection
• X-Content-Type-Options
• Content-Security-Policy
• X-Permitted-Cross-Domain-Policies
• Referrer-Policy
• Expect-CT
• Feature-Policy

HTTP Strict Transport Security (HSTS)

HTTP Strict Transport Security (HSTS) is a web security policy mechanism which helps to protect websites against protocol downgrade attacks and cookie hijacking. It allows web servers to declare that web browsers (or other complying user agents) should only interact with it using secure HTTPS connections, and never via the insecure HTTP protocol. HSTS is an IETF standards track protocol and is specified in RFC 6797. A server implements an HSTS policy by supplying a header (Strict-Transport-Security) over an HTTPS connection (HSTS headers over HTTP are ignored).

Values

Value	Description
max-age=SECONDS	The time, in seconds, that the browser should remember that this site is only to be accessed using HTTPS.
includeSubDomains	If this optional parameter is specified, this rule applies to all of the site's subdomains as well.

Example

Strict-Transport-Security: max-age=31536000 ; includeSubDomains

References

• https://tools.ietf.org/html/rfc6797
• https://www.owasp.org/index.php/HTTP_Strict_Transport_Security
• https://www.owasp.org/index.php/Test_HTTP_Strict_Transport_Security_(OTG-CONFIG-007)
• https://en.wikipedia.org/wiki/HTTP_Strict_Transport_Security
• https://www.chromium.org/hsts
• https://developer.mozilla.org/en-US/docs/Web/Security/HTTP_strict_transport_security
• https://raymii.org/s/tutorials/HTTP_Strict_Transport_Security_for_Apache_NGINX_and_Lighttpd.html

Public Key Pinning Extension for HTTP (HPKP)

HTTP Public Key Pinning (HPKP) is a security mechanism which allows HTTPS websites to resist impersonation by attackers using mis-issued or otherwise fraudulent certificates. (For example, sometimes attackers can compromise certificate authorities, and then can mis-issue certificates for a web origin.).

The HTTPS web server serves a list of public key hashes, and on subsequent connections clients expect that server to use one or more of those public keys in its certificate chain. Deploying HPKP safely will require operational and organizational maturity due to the risk that hosts may make themselves unavailable by pinning to a set of public key hashes that becomes invalid. With care, host operators can greatly reduce the risk of man-in-the-middle (MITM) attacks and other false authentication problems for their users without incurring undue risk.

Before implement HPKP please read this https://www.chromestatus.com/feature/5903385005916160.

Values

Value	Description
pin-sha256="<sha256>"	The quoted string is the Base64 encoded Subject Public Key Information (SPKI) fingerprint. It is possible to specify multiple pins for different public keys. Some browsers might allow other hashing algorithms than SHA-256 in the future.
max-age=SECONDS	The time, in seconds, that the browser should remember that this site is only to be accessed using one of the pinned keys.
includeSubDomains	If this optional parameter is specified, this rule applies to all of the site's subdomains as well.
report-uri="<URL>"	If this optional parameter is specified, pin validation failures are reported to the given URL.

Example

Public-Key-Pins: pin-sha256="d6qzRu9zOECb90Uez27xWltNsj0e1Md7GkYYkVoZWmM="; pin-sha256="E9CZ9INDbd+2eRQozYqqbQ2yXLVKB9+xcprMF+44U1g="; report-uri="http://example.com/pkp-report"; max-age=10000; includeSubDomains

References

• https://tools.ietf.org/html/rfc7469
• https://www.owasp.org/index.php/Certificate_and_Public_Key_Pinning#HTTP_pinning
• https://en.wikipedia.org/wiki/HTTP_Public_Key_Pinning
• https://developer.mozilla.org/en-US/docs/Web/Security/Public_Key_Pinning
• https://raymii.org/s/articles/HTTP_Public_Key_Pinning_Extension_HPKP.html
• https://labs.detectify.com/2016/07/05/what-hpkp-is-but-isnt/
• https://blog.qualys.com/ssllabs/2016/09/06/is-http-public-key-pinning-dead
• https://scotthelme.co.uk/im-giving-up-on-hpkp/
• https://groups.google.com/a/chromium.org/forum/m/#!msg/blink-dev/he9tr7p3rZ8/eNMwKPmUBAAJ

X-Frame-Options

X-Frame-Options response header improve the protection of web applications against Clickjacking. It declares a policy communicated from a host to the client browser on whether the browser must not display the transmitted content in frames of other web pages.

Values

Value	Description
deny	No rendering within a frame.
sameorigin	No rendering if origin mismatch.
allow-from: DOMAIN	Allows rendering if framed by frame loaded from DOMAIN.

Example

X-Frame-Options: deny

References

• https://tools.ietf.org/html/rfc7034
• https://tools.ietf.org/html/draft-ietf-websec-x-frame-options-01
• https://tools.ietf.org/html/draft-ietf-websec-frame-options-00
• https://developer.mozilla.org/en-US/docs/Web/HTTP/X-Frame-Options
• https://www.owasp.org/index.php/Clickjacking
• https://blogs.msdn.microsoft.com/ieinternals/2010/03/30/combating-clickjacking-with-x-frame-options/

X-XSS-Protection

This header enables the Cross-site scripting (XSS) filter in your browser.

Values

Value	Description
0	Filter disabled.
1	Filter enabled. If a cross-site scripting attack is detected, in order to stop the attack, the browser will sanitize the page.
1; mode=block	Filter enabled. Rather than sanitize the page, when a XSS attack is detected, the browser will prevent rendering of the page.
1; report=http://[YOURDOMAIN]/your_report_URI	Filter enabled. The browser will sanitize the page and report the violation. This is a Chromium function utilizing CSP violation reports to send details to a URI of your choice.

Example

X-XSS-Protection: 1; mode=block

References

• https://www.owasp.org/index.php/Cross-site_Scripting_(XSS)
• https://www.virtuesecurity.com/blog/understanding-xss-auditor/
• https://www.veracode.com/blog/2014/03/guidelines-for-setting-security-headers
• http://zinoui.com/blog/security-http-headers#x-xss-protection

X-Content-Type-Options

Setting this header will prevent the browser from interpreting files as something else than declared by the content type in the HTTP headers.

Values

Value	Description
nosniff	Will prevent the browser from MIME-sniffing a response away from the declared content-type.

Example

X-Content-Type-Options: nosniff

References

• https://msdn.microsoft.com/en-us/library/gg622941%28v=vs.85%29.aspx
• https://blogs.msdn.microsoft.com/ie/2008/09/02/ie8-security-part-vi-beta-2-update/

Content-Security-Policy

A Content Security Policy (CSP) requires careful tuning and precise definition of the policy. If enabled, CSP has significant impact on the way browsers render pages (e.g., inline JavaScript disabled by default and must be explicitly allowed in policy). CSP prevents a wide range of attacks, including Cross-site scripting and other cross-site injections.

Values

Directive	Description
base-uri	Define the base uri for relative uri.
default-src	Define loading policy for all resources type in case of a resource type dedicated directive is not defined (fallback).
script-src	Define which scripts the protected resource can execute.
object-src	Define from where the protected resource can load plugins.
style-src	Define which styles (CSS) the user applies to the protected resource.
img-src	Define from where the protected resource can load images.
media-src	Define from where the protected resource can load video and audio.
frame-src	Deprecated and replaced by child-src. Define from where the protected resource can embed frames.
child-src	Define from where the protected resource can embed frames.
frame-ancestors	Define from where the protected resource can be embedded in frames.
font-src	Define from where the protected resource can load fonts.
connect-src	Define which URIs the protected resource can load using script interfaces.
manifest-src	Define from where the protected resource can load manifest.
form-action	Define which URIs can be used as the action of HTML form elements.
sandbox	Specifies an HTML sandbox policy that the user agent applies to the protected resource.
script-nonce	Define script execution by requiring the presence of the specified nonce on script elements.
plugin-types	Define the set of plugins that can be invoked by the protected resource by limiting the types of resources that can be embedded.
reflected-xss	Instructs a user agent to activate or deactivate any heuristics used to filter or block reflected cross-site scripting attacks, equivalent to the effects of the non-standard X-XSS-Protection header.
block-all-mixed-content	Prevent user agent from loading mixed content.
upgrade-insecure-requests	Instructs user agent to download insecure resources using HTTPS.
referrer	Define information user agent must send in Referer header.
report-uri	Specifies a URI to which the user agent sends reports about policy violation.
report-to	Specifies a group (defined in Report-To header) to which the user agent sends reports about policy violation.

Example

Content-Security-Policy: script-src 'self'

References

• https://www.w3.org/TR/CSP/
• https://developer.mozilla.org/en-US/docs/Web/Security/CSP
• https://www.owasp.org/index.php/Content_Security_Policy
• https://scotthelme.co.uk/content-security-policy-an-introduction/
• https://report-uri.io
• http://www.cspplayground.com/home
• http://content-security-policy.com

X-Permitted-Cross-Domain-Policies

A cross-domain policy file is an XML document that grants a web client, such as Adobe Flash Player or Adobe Acrobat (though not necessarily limited to these), permission to handle data across domains. When clients request content hosted on a particular source domain and that content make requests directed towards a domain other than its own, the remote domain needs to host a cross-domain policy file that grants access to the source domain, allowing the client to continue the transaction. Normally a meta-policy is declared in the master policy file, but for those who can’t write to the root directory, they can also declare a meta-policy using the X-Permitted-Cross-Domain-Policies HTTP response header.

Values

Value	Description
none	No policy files are allowed anywhere on the target server, including this master policy file.
master-only	Only this master policy file is allowed.
by-content-type	[HTTP/HTTPS only] Only policy files served with Content-Type: text/x-cross-domain-policy are allowed.
by-ftp-filename	[FTP only] Only policy files whose file names are crossdomain.xml (i.e. URLs ending in /crossdomain.xml) are allowed.
all	All policy files on this target domain are allowed.

Example

X-Permitted-Cross-Domain-Policies: none

References

• https://www.adobe.com/devnet-docs/acrobatetk/tools/AppSec/xdomain.html
• https://www.adobe.com/devnet/adobe-media-server/articles/cross-domain-xml-for-streaming.html
• https://www.perpetual-beta.org/weblog/security-headers.html#rule-8470-2-establish-a-cross-domain-meta-policy
• https://danielnixon.org/http-security-headers/
• https://rorsecurity.info/portfolio/new-http-headers-for-more-security
• https://github.com/twitter/secureheaders/issues/88

Referrer-Policy

The Referrer-Policy HTTP header governs which referrer information, sent in the Referer header, should be included with requests made.

Values

Value	Description
no-referrer	The Referer header will be omitted entirely. No referrer information is sent along with requests.
no-referrer-when-downgrade	This is the user agent's default behavior if no policy is specified. The origin is sent as referrer to a-priori as-much-secure destination (HTTPS->HTTPS), but isn't sent to a less secure destination (HTTPS->HTTP).
origin	Only send the origin of the document as the referrer in all cases. The document https://example.com/page.html will send the referrer https://example.com/.
origin-when-cross-origin	Send a full URL when performing a same-origin request, but only send the origin of the document for other cases.
same-origin	A referrer will be sent for same-site origins, but cross-origin requests will contain no referrer information.
strict-origin	Only send the origin of the document as the referrer to a-priori as-much-secure destination (HTTPS->HTTPS), but don't send it to a less secure destination (HTTPS->HTTP).
strict-origin-when-cross-origin	Send a full URL when performing a same-origin request, only send the origin of the document to a-priori as-much-secure destination (HTTPS->HTTPS), and send no header to a less secure destination (HTTPS->HTTP).
unsafe-url	Send a full URL (stripped from parameters) when performing a a same-origin or cross-origin request.

Example

Referrer-Policy: no-referrer

References

• https://www.w3.org/TR/referrer-policy/
• https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Referrer-Policy

Expect-CT

The Expect-CT header is used by a server to indicate that browsers should evaluate connections to the host emitting the header for Certificate Transparency compliance.

Values

Value	Description
report-uri	The optional report-uri directive indicates the URL to which the browser should report Expect-CT failures.
enforce	The optional enforce directive is a valueless directive that, if present, signals to the browser that compliance to the CT Policy should be enforced (rather than report-only) and that the browser should refuse future connections that violate its CT Policy. When both the enforce directive and report-uri directive are present, the configuration is referred to as an "enforce-and-report" configuration, signalling to the browser both that compliance to the CT Policy should be enforced and that violations should be reported.
max-age	The max-age directive specifies the number of seconds after the reception of the Expect-CT header field during which the browser should regard the host from whom the message was received as a Known Expect-CT Host.

Example

Expect-CT: max-age=86400, enforce, report-uri="https://foo.example/report"

References

• https://tools.ietf.org/html/draft-ietf-httpbis-expect-ct-02
• http://httpwg.org/http-extensions/expect-ct.html
• https://scotthelme.co.uk/a-new-security-header-expect-ct/

Feature-Policy

The Feature-Policy header allows developers to selectively enable and disable use of various browser features and APIs..

Values

Value	Description
accelerometer	Controls access to accelerometer sensors on the device.
ambient-light-sensor	Controls access to ambient light sensors on the device.
autoplay	Controls access to autoplay through play() and autoplay.
camera	Controls access to video input devices.
encrypted-media	Controls whether requestMediaKeySystemAccess() is allowed.
fullscreen	Controls whether requestFullscreen() is allowed.
geolocation	Controls access to Geolocation interface.
gyroscope	Controls access to gyroscope sensors on the device.
magnetometer	Controls access to magnetometer sensors on the device.
microphone	Controls access to audio input devices.
midi	Controls access to requestMIDIAccess() method.
payment	Controls access to PaymentRequest interface.
picture-in-picture	Controls access to Picture in Picture.
speaker	Controls access to audio output devices.
usb	Controls access to USB devices.
vibrate	Controls access to vibrate() method.
vr	Controls access to VR displays.

Example

Feature-Policy: vibrate 'none'; geolocation 'none'

References

• https://wicg.github.io/feature-policy/
• https://github.com/WICG/feature-policy/blob/master/features.md
• https://scotthelme.co.uk/a-new-security-header-feature-policy/

Browser Support

	Internet Explorer	Edge	Firefox	Chrome	Safari	Opera	Android
HTTP Strict Transport Security (HSTS)	11	13	47	49	9.1	39	4.4
Public Key Pinning Extension for HTTP (HPKP)	NS	NS	47	49	NS	39	51
X-Frame-Options	8	13	47	49	9.1	39	4.4
X-XSS-Protection	8		NS	4+
X-Content-Type-Options	8		51	1.0	NS	13
Content-Security-Policy	11	13	47	49	9.1	39	4.4
X-Permitted-Cross-Domain-Policies
Referrer-Policy	NS	NS	50	56	NS	43
Expect-CT				61		48
Feature-Policy

NS = Not Supported

+ = Specified version and above

References

• HTTP Strict Transport Security (HSTS)
  • https://blogs.windows.com/msedgedev/2015/06/09/http-strict-transport-security-comes-to-internet-explorer-11-on-windows-8-1-and-windows-7/
  • https://en.wikipedia.org/wiki/HTTP_Strict_Transport_Security
  • https://www.owasp.org/index.php/HTTP_Strict_Transport_Security_Cheat_Sheet
  • http://caniuse.com/#search=HSTS
• Public Key Pinning Extension for HTTP (HPKP)
  • http://caniuse.com/#search=Public%20Key%20Pinning
  • https://groups.google.com/a/chromium.org/forum/m/#!msg/blink-dev/he9tr7p3rZ8/eNMwKPmUBAAJ
• X-Frame-Options
  • http://caniuse.com/#search=X-Frame-Options
• X-XSS-Protection
  • https://wiki.mozilla.org/Security/Features/XSS_Filter
  • https://blogs.msdn.microsoft.com/ieinternals/2011/01/31/controlling-the-xss-filter/
• X-Content-Type-Options
  • https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Content-Type-Options
• Content-Security-Policy
  • http://caniuse.com/#search=Content%20Security%20Policy
• X-Permitted-Cross-Domain-Policies
  • https://www.adobe.com/devnet-docs/acrobatetk/tools/AppSec/xdomain.html
• Referrer-Policy
  • https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Referrer-Policy
• Expect-CT
  • https://www.chromestatus.com/feature/5677171733430272
• Feature-Policy
  • [update needed]

Coming soon... for now check this.

This section cover a list of tools to analyze, develop and administrate HTTP secure headers in order to help achieve more secure and trustworthy web systems.

Analysis Tools	Reference
hsecscan A security scanner for HTTP response headers.	Github: https://github.com/riramar/hsecscan
headers Python script to get some response headers from Alexa top sites file and store in a MySQL database.	Github: https://github.com/oshp/headers/
securityheaders.io There are services out there that will analyse the HTTP response headers of other sites but I also wanted to add a rating system to the results. The HTTP response headers that this site analyses provide huge levels of protection and it's important that sites deploy them. Hopefully, by providing an easy mechanism to assess them, and further information on how to deploy missing headers, we can drive up the usage of security based headers across the web.	Site: https://securityheaders.io/
Mozilla Observatory A Mozilla project designed to help developers, system administrators, and security professionals configure their sites safely and securely.	Site: https://mozilla.github.io/http-observatory-website/
High-Tech Bridge Web Security Scanner An online service that will retrieve and analyse headers syntax and proper configuration in a comprehensive way. It will be able for instance to highlight Public-Key-Pins that matches one certificate of the chain or if Content-Security-Policy contains values that could be unsafe or too permissive.	Site: https://www.htbridge.com/websec/
Check Your Headers Just another web scanner for HTTP response headers.	Site: https://cyh.herokuapp.com/cyh
Recx Security Analyser Chrome extension that allows the inspection of security aspects of a site's HTTP headers, cookies and other key security settings.	Site: https://chrome.google.com/webstore/detail/recx-security-analyser/ljafjhbjenhgcgnikniijchkngljgjda
KickOff While each project you launch may have a different feature set, they often share many of the same performance, SEO and security requirements. This tool aims to automate the process of checking your list of requirements shortly before launch or directly after a deployment.	Site: https://github.com/frickelbruder/kickoff
testssl.sh Easy to use shell script which tests not only SSL/TLS encryption but also checks common headers and analyzes those. Output is screen, JSON, CSV and HTML.	Site: https://github.com/drwetter/testssl.sh

Development Libraries	Language	Reference
secureheaders Security related headers all in one gem.	Ruby	Github: https://github.com/twitter/secureheaders
Security Header Injection Module (SHIM) SHIM is a HTTP module that provides protection for many vulnerabilities by injecting security-specific HTTP headers into ASP.NET web applications.	ASP.NET	Site: https://shim.codeplex.com/
Spring Security Spring Security’s support for adding various security headers to the response.	Java	Site: http://docs.spring.io/spring-security/site/docs/current/reference/html/headers.html
SecureHeaders A PHP class aiming to make the use of browser security features more accessible.	PHP	Site: https://github.com/aidantwoods/SecureHeaders
rack-secure_headers Security related HTTP headers for Rack applications.	Rack	Site: https://github.com/frodsan/rack-secure_headers
helmet and hood Node.js (express).	Node.js (express)	Site: https://github.com/helmetjs/helmet Site: https://github.com/seanmonstar/hood
blankie A CSP plugin for hapi.	Node.js (hapi)	Site: https://github.com/nlf/blankie
NWebsec NWebsec consists of several security libraries for ASP.NET applications.	ASP.NET	Site: https://docs.nwebsec.com
django-csp + commonware; django-security django-csp + commonware; django-security.	Python	Site: https://github.com/mozilla/django-csp Site: https://github.com/jsocol/commonware/ Site: https://github.com/sdelements/django-security
Secure Secure is a lightweight package that adds optional security headers and cookie attributes for Python web frameworks.	Python	Site: https://github.com/cakinney/secure
secureheader Package secureheader adds some HTTP header fields widely considered to improve safety of HTTP requests.	Go	Site: https://github.com/kr/secureheader
secure_headers This Plug will automatically apply several security headers to the Plug.Conn response. By design SecureHeaders will attempt to apply the most strict security policy. Although, security headers are configurable and are validated to avoid misconfiguration.	Elixir	Site: https://github.com/anotherhale/secure_headers
dropwizard-web-security A bundle for applying default web security functionality to a dropwizard application.	Dropwizard	Site: https://github.com/palantir/dropwizard-web-security
ember-cli-content-security-policy This addon makes it easy to use Content Security Policy (CSP) in your project. It can be deployed either via a Content-Security-Policy header sent from the Ember CLI Express server, or as a meta tag in the index.html file.	Ember.js	Site: https://github.com/rwjblue/ember-cli-content-security-policy/

Operation Tools	Web Servers Supported	Reference
http_hardening Puppet module to enable, configure and manage secure http headers on web servers.	Apache HTTP Server NGINX Lighttpd	Github: https://github.com/amenezes/http_hardening Puppet Forge: https://forge.puppet.com/amenezes/http_hardening

HTTP response headers from the top websites in the world.

Command used to extract the headers:

curl -L -A "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/50.0.2661.102 Safari/537.36" -s -D - https://www.example.com -o /dev/null

Google

$ curl -L -A "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/62.0.3202.89 Safari/537.36" -s -D - https://www.google.com -o /dev/null
HTTP/1.1 302 Found
Location: https://www.google.com.br/?gws_rd=cr&dcr=0&ei=rtcKWpnkNYaawATUn6agCg
Cache-Control: private
Content-Type: text/html; charset=UTF-8
P3P: CP="This is not a P3P policy! See g.co/p3phelp for more info."
Date: Tue, 14 Nov 2017 11:46:54 GMT
Server: gws
Content-Length: 273
X-XSS-Protection: 1; mode=block
X-Frame-Options: SAMEORIGIN
Set-Cookie: NID=117=GENZIllQGZFmhCBmap1YThta_hUvvZ9Xm517XXWpF9eCKNqW6_luvZm1b_ai7BN4lAA2pP2Z22BveHqjUrqZxpY38NKSYLKWFGrVh6tGAHcbNw6OHQ_F77bNJWV0BZOZ; expires=Wed, 16-May-2018 11:46:54 GMT; path=/; domain=.google.com; HttpOnly
Alt-Svc: quic=":443"; ma=2592000; v="41,39,38,37,35"

HTTP/1.1 200 OK
Date: Tue, 14 Nov 2017 11:46:55 GMT
Expires: -1
Cache-Control: private, max-age=0
Content-Type: text/html; charset=UTF-8
Strict-Transport-Security: max-age=3600
P3P: CP="This is not a P3P policy! See g.co/p3phelp for more info."
Server: gws
X-XSS-Protection: 1; mode=block
X-Frame-Options: SAMEORIGIN
Set-Cookie: 1P_JAR=2017-11-14-11; expires=Thu, 14-Dec-2017 11:46:55 GMT; path=/; domain=.google.com.br
Set-Cookie: NID=117=fR73jhascV3B9fbiVfYdvGlilR_tgYNhela9rXdCavJiJoYpkNSTq0NtFqNSV8im602zM7Of-S1GUr_ncSuT3p6tzlw3e6_9ccqPttSuniTHWZEgBtUL1VXTgXBdjKMe; expires=Wed, 16-May-2018 11:46:55 GMT; path=/; domain=.google.com.br; HttpOnly
Alt-Svc: quic=":443"; ma=2592000; v="41,39,38,37,35"
Accept-Ranges: none
Vary: Accept-Encoding
Transfer-Encoding: chunked

Facebook

$ curl -L -A "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/62.0.3202.89 Safari/537.36" -s -D - https://www.facebook.com -o /dev/null
HTTP/1.1 200 OK
X-XSS-Protection: 0
Pragma: no-cache
content-security-policy: default-src * data: blob:;script-src *.facebook.com *.fbcdn.net *.facebook.net *.google-analytics.com *.virtualearth.net *.google.com 127.0.0.1:* *.spotilocal.com:* 'unsafe-inline' 'unsafe-eval' fbstatic-a.akamaihd.net fbcdn-static-b-a.akamaihd.net *.atlassolutions.com blob: data: 'self';style-src data: blob: 'unsafe-inline' *;connect-src *.facebook.com *.fbcdn.net *.facebook.net *.spotilocal.com:* *.akamaihd.net wss://*.facebook.com:* https://fb.scanandcleanlocal.com:* *.atlassolutions.com attachment.fbsbx.com ws://localhost:* blob: *.cdninstagram.com 'self' chrome-extension://boadgeojelhgndaghljhdicfkmllpafd chrome-extension://dliochdbjfkdbacpmhlcpmleaejidimm;
Cache-Control: private, no-cache, no-store, must-revalidate
X-Frame-Options: DENY
expect-ct: max-age=10, report-uri="http://reports.fb.com/expectct/"
Strict-Transport-Security: max-age=15552000; preload
X-Content-Type-Options: nosniff
Expires: Sat, 01 Jan 2000 00:00:00 GMT
Set-Cookie: fr=0Bf96eRMD0zCulvzh..BaCtgp.jl.AAA.0.0.BaCtgp.AWVGQojt; expires=Mon, 12-Feb-2018 11:48:57 GMT; Max-Age=7776000; path=/; domain=.facebook.com; secure; httponly
Set-Cookie: sb=KdgKWqMf8J84KfUg99AxaG1B; expires=Thu, 14-Nov-2019 11:48:57 GMT; Max-Age=63072000; path=/; domain=.facebook.com; secure; httponly
Vary: Accept-Encoding
Content-Type: text/html; charset=UTF-8
X-FB-Debug: llncdeFRYCCoWkXqx2VCdUGtdHZvjsr6OA7JNrtEe18ZuZAqcKCH4km9SSkNTHIcuXmzwRMzyBQt0Uz7T6ltQg==
Date: Tue, 14 Nov 2017 11:48:57 GMT
Transfer-Encoding: chunked
Connection: keep-alive

Twitter

$ curl -L -A "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/62.0.3202.89 Safari/537.36" -s -D - https://www.twitter.com -o /dev/null
HTTP/1.1 301 Moved Permanently
content-length: 0
date: Tue, 14 Nov 2017 11:50:11 GMT
location: https://twitter.com/
server: tsa_d
set-cookie: personalization_id="v1_nyz+ctxxDiBbh4s6VjzQIg=="; Expires=Thu, 14 Nov 2019 11:50:11 UTC; Path=/; Domain=.twitter.com
set-cookie: guest_id=v1%3A151066021116455299; Expires=Thu, 14 Nov 2019 11:50:11 UTC; Path=/; Domain=.twitter.com
strict-transport-security: max-age=631138519
x-connection-hash: d9a9eea848268dae67e7743d5bfd2dd5
x-response-time: 135

HTTP/1.1 200 OK
cache-control: no-cache, no-store, must-revalidate, pre-check=0, post-check=0
content-length: 345977
content-security-policy: script-src https://connect.facebook.net https://cm.g.doubleclick.net https://ssl.google-analytics.com https://graph.facebook.com 'nonce-f/+1f61E6Z0qq8p+L4UIQw==' https://twitter.com 'unsafe-eval' https://*.twimg.com https://api.twitter.com https://analytics.twitter.com https://publish.twitter.com https://ton.twitter.com https://syndication.twitter.com https://www.google.com https://t.tellapart.com https://platform.twitter.com https://www.google-analytics.com blob: 'self'; frame-ancestors 'self'; font-src https://twitter.com https://*.twimg.com data: https://ton.twitter.com https://fonts.gstatic.com https://maxcdn.bootstrapcdn.com https://netdna.bootstrapcdn.com 'self'; media-src https://rmpdhdsnappytv-vh.akamaihd.net https://prod-video-eu-central-1.pscp.tv https://v.cdn.vine.co https://dwo3ckksxlb0v.cloudfront.net https://twitter.com https://amp.twimg.com https://smmdhdsnappytv-vh.akamaihd.net https://*.twimg.com https://prod-video-eu-west-1.pscp.tv https://rmmdhdsnappytv-vh.akamaihd.net https://prod-video-us-west-2.pscp.tv https://prod-video-us-west-1.pscp.tv https://prod-video-ap-northeast-1.pscp.tv https://smdhdsnappytv-vh.akamaihd.net https://ton.twitter.com https://rmdhdsnappytv-vh.akamaihd.net https://mmdhdsnappytv-vh.akamaihd.net https://smpdhdsnappytv-vh.akamaihd.net https://prod-video-sa-east-1.pscp.tv https://mdhdsnappytv-vh.akamaihd.net https://prod-video-ap-southeast-2.pscp.tv https://mtc.cdn.vine.co https://dev-video-us-west-2.pscp.tv https://prod-video-us-east-1.pscp.tv blob: 'self' https://prod-video-ap-southeast-1.pscp.tv https://mpdhdsnappytv-vh.akamaihd.net https://dev-video-eu-west-1.pscp.tv; connect-src https://rmpdhdsnappytv-vh.akamaihd.net https://prod-video-eu-central-1.pscp.tv https://graph.facebook.com https://*.giphy.com https://dwo3ckksxlb0v.cloudfront.net https://vmaprel.snappytv.com https://smmdhdsnappytv-vh.akamaihd.net https://*.twimg.com https://embed.pscp.tv https://api.twitter.com https://prod-video-eu-west-1.pscp.tv https://rmmdhdsnappytv-vh.akamaihd.net https://prod-video-us-west-2.pscp.tv https://pay.twitter.com https://prod-video-us-west-1.pscp.tv https://analytics.twitter.com https://vmap.snappytv.com https://*.twprobe.net https://prod-video-ap-northeast-1.pscp.tv https://smdhdsnappytv-vh.akamaihd.net https://syndication.twitter.com https://sentry.io https://rmdhdsnappytv-vh.akamaihd.net https://media.riffsy.com https://mmdhdsnappytv-vh.akamaihd.net https://embed.periscope.tv https://smpdhdsnappytv-vh.akamaihd.net https://prod-video-sa-east-1.pscp.tv https://vmapstage.snappytv.com https://upload.twitter.com https://proxsee.pscp.tv https://mdhdsnappytv-vh.akamaihd.net https://prod-video-ap-southeast-2.pscp.tv https://dev-video-us-west-2.pscp.tv https://prod-video-us-east-1.pscp.tv 'self' https://vmap.grabyo.com https://prod-video-ap-southeast-1.pscp.tv https://mpdhdsnappytv-vh.akamaihd.net https://dev-video-eu-west-1.pscp.tv; style-src https://fonts.googleapis.com https://twitter.com https://*.twimg.com https://translate.googleapis.com https://ton.twitter.com 'unsafe-inline' https://platform.twitter.com https://maxcdn.bootstrapcdn.com https://netdna.bootstrapcdn.com 'self'; object-src https://twitter.com https://pbs.twimg.com; default-src 'self'; frame-src https://staticxx.facebook.com https://twitter.com https://*.twimg.com https://5415703.fls.doubleclick.net https://player.vimeo.com https://pay.twitter.com https://www.facebook.com https://ton.twitter.com https://syndication.twitter.com https://vine.co twitter: https://www.youtube.com https://platform.twitter.com https://upload.twitter.com https://s-static.ak.facebook.com https://4337974.fls.doubleclick.net https://8122179.fls.doubleclick.net 'self' https://donate.twitter.com; img-src https://prod-video-eu-central-1.pscp.tv https://prod-profile.pscp.tv https://graph.facebook.com https://prod-thumbnail.pscp.tv https://*.giphy.com https://twitter.com https://*.twimg.com https://ad.doubleclick.net https://prod-video-eu-west-1.pscp.tv data: https://prod-video-us-west-2.pscp.tv https://prod-video-us-west-1.pscp.tv https://prod-video-ap-northeast-1.pscp.tv https://lumiere-a.akamaihd.net https://fbcdn-profile-a.akamaihd.net https://www.facebook.com https://ton.twitter.com https://*.fbcdn.net https://syndication.twitter.com https://media.riffsy.com https://www.google.com https://prod-profile.periscope.tv https://prod-video-sa-east-1.pscp.tv https://stats.g.doubleclick.net https://platform.twitter.com https://prod-video-ap-southeast-2.pscp.tv https://api.mapbox.com https://www.google-analytics.com https://dev-video-us-west-2.pscp.tv https://prod-video-us-east-1.pscp.tv blob: https://prod-thumbnail-small.pscp.tv https://prod-thumbnail-small.periscope.tv 'self' https://prod-thumbnail.periscope.tv https://prod-video-ap-southeast-1.pscp.tv https://dev-video-eu-west-1.pscp.tv; report-uri https://twitter.com/i/csp_report?a=NVQWGYLXFVZXO2LGOQ%3D%3D%3D%3D%3D%3D&ro=false;
content-type: text/html;charset=utf-8
date: Tue, 14 Nov 2017 11:50:11 GMT
expires: Tue, 31 Mar 1981 05:00:00 GMT
last-modified: Tue, 14 Nov 2017 11:50:11 GMT
pragma: no-cache
server: tsa_d
set-cookie: fm=0; Expires=Tue, 14 Nov 2017 11:50:02 UTC; Path=/; Domain=.twitter.com; Secure; HTTPOnly
set-cookie: _twitter_sess=BAh7CSIKZmxhc2hJQzonQWN0aW9uQ29udHJvbGxlcjo6Rmxhc2g6OkZsYXNo%250ASGFzaHsABjoKQHVzZWR7ADoPY3JlYXRlZF9hdGwrCMOCXbpfAToMY3NyZl9p%250AZCIlOTk3MjYzYzc1NDhkOTA1ZTlhZTIyNGE2Zjk5Nzg0NTk6B2lkIiU0ODIw%250AZWRkNjc4Njg2M2IzYmI3ZTA3N2YxMTA4YzE5Nw%253D%253D--7abf7eef950088f9f728686ce29881ef501487dd; Path=/; Domain=.twitter.com; Secure; HTTPOnly
set-cookie: personalization_id="v1_rrHzrB5h0Qs1Oz4uhOjFJg=="; Expires=Thu, 14 Nov 2019 11:50:11 UTC; Path=/; Domain=.twitter.com
set-cookie: guest_id=v1%3A151066021139105511; Expires=Thu, 14 Nov 2019 11:50:11 UTC; Path=/; Domain=.twitter.com
set-cookie: ct0=ba98c8a6cb4c664151a98c8bd9eb4b4d; Expires=Tue, 14 Nov 2017 17:50:11 UTC; Path=/; Domain=.twitter.com; Secure
status: 200 OK
strict-transport-security: max-age=631138519
x-connection-hash: 769f9dcd87b9274776136b99b3181a44
x-content-type-options: nosniff
x-frame-options: SAMEORIGIN
x-response-time: 359
x-transaction: 007d216900cbc2ad
x-twitter-response-tags: BouncerCompliant
x-ua-compatible: IE=edge,chrome=1
x-xss-protection: 1; mode=block

Github

$ curl -L -A "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/62.0.3202.89 Safari/537.36" -s -D - https://www.github.com -o /dev/null
HTTP/1.1 301 Moved Permanently
Content-length: 0
Location: https://github.com/

HTTP/1.1 200 OK
Server: GitHub.com
Date: Tue, 14 Nov 2017 11:51:27 GMT
Content-Type: text/html; charset=utf-8
Transfer-Encoding: chunked
Status: 200 OK
Cache-Control: no-cache
Vary: X-PJAX
X-UA-Compatible: IE=Edge,chrome=1
Set-Cookie: logged_in=no; domain=.github.com; path=/; expires=Sat, 14 Nov 2037 11:51:27 -0000; secure; HttpOnly
Set-Cookie: _gh_sess=eyJzZXNzaW9uX2lkIjoiODI5ZGZjZDhlZDFlMjBjZTBhMTljMjk5ZDU1ZDBlODgiLCJsYXN0X3JlYWRfZnJvbV9yZXBsaWNhcyI6MTUxMDY2MDI4NzMxNywiX2NzcmZfdG9rZW4iOiIvTjkya2RHLzJJN2dtbU12eWQ3UGJDeTJ0aU1tZHJrci8wVzlpMi9yajFZPSJ9--5920790d2e11e8d4a32177a14ac25fae6e8f9789; path=/; secure; HttpOnly
X-Request-Id: b31804a05047fd1326fe28cf3d6f33aa
X-Runtime: 0.036845
Expect-CT: max-age=2592000, report-uri="https://api.github.com/_private/browser/errors"
Content-Security-Policy: default-src 'none'; base-uri 'self'; block-all-mixed-content; child-src render.githubusercontent.com; connect-src 'self' uploads.github.com status.github.com collector.githubapp.com api.github.com www.google-analytics.com github-cloud.s3.amazonaws.com github-production-repository-file-5c1aeb.s3.amazonaws.com github-production-upload-manifest-file-7fdce7.s3.amazonaws.com github-production-user-asset-6210df.s3.amazonaws.com wss://live.github.com; font-src assets-cdn.github.com; form-action 'self' github.com gist.github.com; frame-ancestors 'none'; img-src 'self' data: assets-cdn.github.com identicons.github.com collector.githubapp.com github-cloud.s3.amazonaws.com *.githubusercontent.com; media-src 'none'; script-src assets-cdn.github.com; style-src 'unsafe-inline' assets-cdn.github.com
Strict-Transport-Security: max-age=31536000; includeSubdomains; preload
Public-Key-Pins: max-age=0; pin-sha256="WoiWRyIOVNa9ihaBciRSC7XHjliYS9VwUGOIud4PB18="; pin-sha256="RRM1dGqnDFsCJXBTHky16vi1obOlCgFFn/yOhI/y+ho="; pin-sha256="k2v657xBsOVe1PQRwOsHsw3bsGT2VzIqz5K+59sNQws="; pin-sha256="K87oWBWM9UZfyddvDfoxL+8lpNyoUB2ptGtn0fv6G2Q="; pin-sha256="IQBnNBEiFuhj+8x6X8XLgh01V9Ic5/V3IRQLNFFc7v4="; pin-sha256="iie1VXtL7HzAMF+/PVPR9xzT80kQxdZeJ+zduCB3uj0="; pin-sha256="LvRiGEjRqfzurezaWuj8Wie2gyHMrW5Q06LspMnox7A="; includeSubDomains
X-Content-Type-Options: nosniff
X-Frame-Options: deny
X-XSS-Protection: 1; mode=block
X-Runtime-rack: 0.043225
X-GitHub-Request-Id: 9AB0:25783:6A523:B814E:5A0AD8BE

Please note the best practices below suggest methods to change webserver configuration to add headers. Security headers can also be successfully added to your application at the software level as well in almost every web language. Many web frameworks add some of these headers automatically.

Response Headers

• HTTP Strict Transport Security (HSTS)
• Public Key Pinning Extension for HTTP (HPKP)
• X-Frame-Options
• X-XSS-Protection
• X-Content-Type-Options
• Content-Security-Policy
• X-Permitted-Cross-Domain-Policies
• Referrer-Policy
• Expect-CT
• Feature-Policy

HTTP Strict Transport Security (HSTS)

• Apache

Edit your apache configuration file and add the following to your VirtualHost.

Header always set Strict-Transport-Security "max-age=63072000; includeSubdomains"

• nginx

Edit your nginx configuration file and add the following snippet.

add_header Strict-Transport-Security "max-age=63072000; includeSubdomains";

• lighttpd

Edit your lighttpd configuration file and add the following snippet.

setenv.add-response-header = ("Strict-Transport-Security" => "max-age=63072000; includeSubdomains",)

• IIS

Visit https://scotthelme.co.uk/hardening-your-http-response-headers/#strict-transport-security

Public Key Pinning Extension for HTTP (HPKP)

• Apache

Edit your apache configuration file and add the following to your VirtualHost.

Header set Public-Key-Pins "pin-sha256=\"klO23nT2ehFDXCfx3eHTDRESMz3asj1muO+4aIdjiuY=\"; pin-sha256=\"633lt352PKRXbOwf4xSEa1M517scpD3l5f79xMD9r9Q=\"; max-age=2592000; includeSubDomains"

• nginx

Edit your nginx configuration file and add the following snippet.

add_header Public-Key-Pins "pin-sha256=\"klO23nT2ehFDXCfx3eHTDRESMz3asj1muO+4aIdjiuY=\"; pin-sha256=\"633lt352PKRXbOwf4xSEa1M517scpD3l5f79xMD9r9Q=\"; max-age=2592000; includeSubDomains";

• lighttpd

Edit your lighttpd configuration file and add the following snippet.

setenv.add-response-header = ("Public-Key-Pins" => "pin-sha256=\"klO23nT2ehFDXCfx3eHTDRESMz3asj1muO+4aIdjiuY=\"; pin-sha256=\"633lt352PKRXbOwf4xSEa1M517scpD3l5f79xMD9r9Q=\"; max-age=2592000; includeSubDomains",)

• IIS

Visit https://scotthelme.co.uk/hardening-your-http-response-headers/#public-key-pinning

X-Frame-Options

• Apache

Add this line below into your site's configuration to configure Apache to send X-Frame-Options header for all pages.

Header set X-Frame-Options "DENY"

• nginx

Add snippet below into configuration file to send X-Frame-Options header.

add_header X-Frame-Options "DENY";

• lighttpd

Add snippet below into configuration file to send X-Frame-Options header.

setenv.add-response-header = ("X-Frame-Options" => "DENY",)

• IIS

Visit https://scotthelme.co.uk/hardening-your-http-response-headers/#x-frame-options

X-XSS-Protection

Add appropriate snippet into configuration file.

• Apache

Header set X-XSS-Protection "1; mode=block"

• nginx

add_header X-XSS-Protection "1;mode=block";

• lighttpd

setenv.add-response-header = ("X-XSS-Protection" => "1; mode=block",)

• IIS

Visit https://scotthelme.co.uk/hardening-your-http-response-headers/#x-xss-protection

X-Content-Type-Options

Add appropriate snippet into configuration file.

• Apache

Header set X-Content-Type-Options "nosniff"

• nginx

add_header X-Content-Type-Options "nosniff";

• lighttpd

setenv.add-response-header = ("X-Content-Type-Options" => "nosniff",)

• IIS

Visit https://scotthelme.co.uk/hardening-your-http-response-headers/#x-content-type-options

Content-Security-Policy

Add appropriate snippet into configuration file.

• Apache

Header set Content-Security-Policy "script-src 'self'; object-src 'self'"

• nginx

add_header Content-Security-Policy "script-src 'self'; object-src 'self'";

• lighttpd

setenv.add-response-header = ("Content-Security-Policy" => "script-src 'self'; object-src 'self'",)

• IIS

Visit https://scotthelme.co.uk/hardening-your-http-response-headers/#content-security-policy

X-Permitted-Cross-Domain-Policies

Add appropriate snippet into configuration file.

• Apache

Header set X-Permitted-Cross-Domain-Policies "none"

• nginx

add_header X-Permitted-Cross-Domain-Policies "none";

• lighttpd

setenv.add-response-header = ("X-Permitted-Cross-Domain-Policies" => "none",)

• IIS

[update needed]

Referrer-Policy

• Apache

[update needed]

• nginx

[update needed]

• lighttpd

[update needed]

• IIS

[update needed]

Expect-CT

• Apache

[update needed]

• nginx

[update needed]

• lighttpd

[update needed]

• IIS

[update needed]

Feature-Policy

Disables camera, microphone, and payment API. More features can be added to restrict if desired (vr, midi, etc).

• Apache

Header set Feature-Policy: camera: 'none'; payment: 'none'; microphone: 'none'

• nginx

[update needed]

• lighttpd

[update needed]

• IIS

[update needed]

What is HTTP header?

HTTP header fields are part of HTTP message defined in RFC 2616 that consists of requests from client to server and responses from server to client that define parameters for the communication process including: language, compression support, security and a lot of resources.

Is there a standard for HTTP headers?

A core set of fields is standardized by the Internet Engineering Task Force (IETF) in RFCs 7230, 7231, 7232, 7233, 7234, and 7235. The permanent registry of header fields and repository of provisional registrations are maintained by the IANA. Additional field names and permissible values may be defined by each application. Non-standard header fields were conventionally marked by prefixing the field name with X- but this convention was deprecated in June 2012 because of the inconveniences it caused when non-standard fields became standard. An earlier restriction on use of Downgraded- was lifted in March 2013.

Why I need worry about that?

Like other initiatives supported by OWASP, this project have the objetive to help all community to conceive, develop, acquire, operate and maintain applications that can be trusted as provide useful information about the use relative of secure http headers by applications and platforms supported.

Where can apply secure features presented by this project?

The effectiveness provides by secure http headers demands that application or some component of infrastructure indicate proper header and correspondent value as like use of some client that implement that feature.

When I consider apply this improvements?

The short response it's right now. However we believe in approach more responsible. So we recommend conducting a planning and preliminary study, as well the incremental inclusion of insurance headers.

Headers like: Public Key Pinning Extension for HTTP (HPKP), HTTP Strict Transport Security (HSTS) and Content Security Policy (CSP) need a special attention in order not to cause any incident. Some real cases about to use of secure headers can be seen:

- Secure websites shun HTTP Public Key Pinning

- HTTP Public Key Pinning: You’re doing it wrong!

- CSP On Reporting and Filtering

- Content Security Policy (CSP)

Who can be responsible to apply secure features?

The responsability to provides more secure environment it's a effort that envolve developers, system administrators, vendors of web browsers and end user.

Like this the success of secure headers strategy depends of proper client, in general a web browser, and web application or some infrastructure component configured appropriately.

How can I apply secure http headers?

The use of secure headers can occur directly through of handling http response headers or using some framework, in addition to conducting appropriate configuration in web server.

The OWASP: Secure Headers project provides a list of resources and examples to help understand, analyze and configure secure headers.

What's the costs relative to apply this actions?

There's no costs in to use secure headers. However some effort to configure and manage properly configuration will be necessary.

Contributors

OWASP Secure Headers Project is developed by a worldwide team of volunteers. The primary contributors to date have been:

• Ricardo Iramar
• Jim Manico
• Alexandre Menezes

Involvement in the development and promotion of OWASP Secure Headers Project is actively encouraged! You do not have to be a security expert in order to contribute. If you want to help send an email to [email protected].

To Do

• Perform public to scan websites and view stats regarding these headers. Automated scanning of the top 1m sites on the web; filtering of said sites to view stats across industries and countries; published database dumps for public consumption/tools; scanning of individual sites; comparing multiple scanned sites.
• Consistent reports regarding this secure headers, their usage, any changes to existing headers.
• Reorganize "Best Practices" tab and include a section for related security best practices around headers (e.g. "Remove Server Header" and "Remove X-Powered-By Header").
• Create a parser to grab the headers from https://scans.io and populate the MySQL database.

Doing

• Producing open source, easily implemented, well documented code libraries that enable these headers for a variety of platforms. We'll prioritize creating and publicizing Node.JS, PHP, Ruby, and Java, but will eventually reach out towards edge cases like Go, Python and others. The key is to make this accessible as possible to developers.
• Including how to set properly secure headers on IIS.
• Improve constantly hsecscan tool to detect bad practices and provide link to the best practices above.

Done

• Creating secure best practices implementations including how to set properly secure headers on the most common platforms (eg. Apache, NGINX and Lighttpd).
• Divide the "Tools_and_Libraries" tab into two differents tab (Scanners and Libraries).
• Include link to attack pages.
• Include Top Websites Examples tab.
• Move the Best Practices to another tab.
• Include a new tab only for browser versions compatibility.
• Include X-Permitted-Cross-Domain-Policies under Headers and Best Practices tab.
• Include Expect-CT header and update HPKP.
• Include Feature-Policy.