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Difference between revisions of "Talk:Securing tomcat"

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== Installation ==
+
== InvokerServlet ==
* Choose an installation directory (referenced as '''TOMCAT_DIR''' from now on), preferably on a different drive to the OS.
+
There needs to be an addendum in here about disabling the InvokerServlet. See my blog entry at [[http://yet-another-dev.blogspot.com/2009/12/this-post-is-especially-for-anyone.html yet-another-dev.blogspot.com]] for details about why this is a bad idea. --[[User:Chris Schmidt|Chris Schmidt]] 22:03, 17 December 2009 (UTC)
  do we get many advantages separating application and webapps?''
 
  - it could prevent path traversal under windows, but not unix. Separating apps from OS is common good practice anyway. [[User:Stephendv|Stephendv]] 02:32, 9 October 2006 (EDT)
 
* Change the default HTTP port to something other than 8080. This ensures less scripted attacks on your server, but in no way helps protect you from vulnerabilities.
 
  - As you say, there's probably not any real benefit to recommending this.  [[User:Stephendv|Stephendv]] 02:32, 9 October 2006 (EDT)
 
  
== Network Security ==
+
== File permissions ==
  
Generic advice common to all server security (link).
+
Hmm, what does "Make sure tomcat user has read/write access to /tmp" mean?  
  - Not sure what information should go here? [[User:Stephendv|Stephendv]] 04:21, 16 October 2006 (EDT)
 
  
== User Input ==
+
Tomcat creates a directory "temp", not "tmp", and read/write on a directory doesn't actually allow reading or writing.  I assume the intention is "chmod 700 temp"... would love if anyone can clarify.
 +
[[User:Douglasheld|Douglasheld]] 18:06, 3 April 2009 (UTC)
  
User data, whether it be HTTP headers or parameters, should '"never"' be trusted.  It is usually the responsibility of the application to validate data, but it is important that one poorly written application doesn't compromise Tomcat as a whole.
+
== Newer Tomcat branches ==
  
* global filters
+
This page is hopelessly outdated for anyone working with the Tomcat 6 branch.  We need to figure out the best way to document security measures for the different supported branches.
* global error pages (see above)
+
[[User:Ken|Ken]] 10:25, 20 March 2009 (UTC)
* permission lockdown (see below)
 
  
  - I think this section would be more appropriate for apps themselves, rather than applying to the server as a whole.
+
I've not had call to use Tomcat 6, but in a few months I plan to start experimenting with the embedded version.  I don't mind expanding the article to have a section on 6 (and keep the section on 5.5), but I can't contribute anything just yet.  My preference would be a single article as it will cut down on duplication.  In the meantime, any differences, areas to cover, new features, etc. that others could note down will help speed things up. [[User:Dledmonds|Darren]] 09:11, 26 March 2009 (UTC)
 +
 
 +
== HttpOnly configuration ==
 +
 
 +
Tomcat versions from 5.5.28 and 6.0.19 support the HttpOnly [http://www.owasp.org/index.php/HttpOnly] cookie option.
 +
 
 +
This is configured in the conf/context.xml file:
 +
 
 +
<Context useHttpOnly="true">
 +
...
 +
</Context>
 +
 
 +
[[User:Simon Bennetts|Simon Bennetts]] 14:40, 18 June 2010 (UTC)
 +
 
 +
== Overriding Tomcat Version Number ==
 +
 
 +
Rebuilding the catalina.jar to alter ServerInfo.properties may not be an ideal way to override the version number, the same effect can be achieved without repackaging JARs in the default distribution (repackaging can be somewhat intrusive and/or impractical). Classloader classpaths can be patched using strategically placed files on the classpath. Classes that are loaded first always take precedence, the same goes for properties files, hence you can override by creating files in the following places:
 +
 
 +
# For Tomcat 5.5 (inject your new file onto the path of the server classloader):
 +
${catalina.home}/server/classes/org/apache/catalina/util/ServerInfo.properties
 +
 
 +
# For Tomcat 6 (inject it onto the path of the common classloader, or whichever classloader is loading catalina.jar):
 +
${catalina.home}/lib/org/apache/catalina/util/ServerInfo.properties
 +
 
 +
In both cases, ${catalina.home} is typically either the root of your local installation, or your global installation if you are making use of disjoint installs using ${catalina.base} to provide instance-specific information.
 +
 
 +
== autoDeploy feature ==
 +
 
 +
Wouldn't it make sense to disable the autoDeploy feature in production environments for added security?
 +
 
 +
[[User:Pierre Ernst|Pierre Ernst]] 2011-08-12
 +
 
 +
== Disabling weak ciphers in Tomcat ==
 +
 
 +
Copied from [https://support.comodo.com/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=1225]
 +
 
 +
In order to disable weak ciphers, please modify your SSL Connector container attribute inside server.xml with the following information.
 +
 
 +
ciphers="SSL_RSA_WITH_RC4_128_SHA, TLS_RSA_WITH_AES_128_CBC_SHA,
 +
  TLS_DHE_RSA_WITH_AES_128_CBC_SHA, TLS_DHE_DSS_WITH_AES_128_CBC_SHA,
 +
  SSL_RSA_WITH_3DES_EDE_CBC_SHA, SSL_DHE_RSA_WITH_3DES_EDE_CBC_SHA,
 +
  SSL_DHE_DSS_WITH_3DES_EDE_CBC_SHA"
 +
 
 +
Example:
 +
 
 +
<Connector port="443" maxHttpHeaderSize="8192" address="192.168.1.1"
 +
enableLookups="false" disableUploadTimeout="true"
 +
acceptCount="100" scheme="https" secure="true"
 +
clientAuth="false" sslProtocol="SSL"
 +
ciphers="SSL_RSA_WITH_RC4_128_SHA, TLS_RSA_WITH_AES_128_CBC_SHA,
 +
  TLS_DHE_RSA_WITH_AES_128_CBC_SHA, TLS_DHE_DSS_WITH_AES_128_CBC_SHA,
 +
  SSL_RSA_WITH_3DES_EDE_CBC_SHA, SSL_DHE_RSA_WITH_3DES_EDE_CBC_SHA, 
 +
  SSL_DHE_DSS_WITH_3DES_EDE_CBC_SHA
 +
keystoreFile="SomeDir/SomeFile.key" keystorePass="Poodle"
 +
truststoreFile="SomeDir/SomeFile.truststore" truststorePass="HomeRun"/>
 +
 
 +
[[User:Psiinon]] 2011-10-06
 +
 
 +
[[User:Dirk Wetter]] 2014-03-27 : Those ciphers were maybe ok in 2011, in 2014 I would not recommend using RC4 and CBC ciphers!
 +
 
 +
==  No missing steps required in Tomcat 7 or 8 ==
 +
I've done some research and as far as I can tell there are no recommended hardening steps for Tomcat 7 or 8 missing from this guide.
 +
 
 +
http://tomcat.apache.org/tomcat-7.0-doc/security-howto.html#Securing_Management_Applications
 +
http://chandank.com/application-server/tomcat/apache-tomcat-hardening-and-security-guide
 +
 
 +
The SSL Cipher list should be upgraded however:
 +
http://www.sslshopper.com/article-how-to-disable-weak-ciphers-and-ssl-2-in-tomcat.html
 +
 
 +
[[User:Kenneth Kron|Kenneth Kron]] ([[User talk:Kenneth Kron|talk]]) 16:56, 22 August 2014 (CDT)

Latest revision as of 00:38, 23 August 2014

InvokerServlet

There needs to be an addendum in here about disabling the InvokerServlet. See my blog entry at [yet-another-dev.blogspot.com] for details about why this is a bad idea. --Chris Schmidt 22:03, 17 December 2009 (UTC)

File permissions

Hmm, what does "Make sure tomcat user has read/write access to /tmp" mean?

Tomcat creates a directory "temp", not "tmp", and read/write on a directory doesn't actually allow reading or writing. I assume the intention is "chmod 700 temp"... would love if anyone can clarify. Douglasheld 18:06, 3 April 2009 (UTC)

Newer Tomcat branches

This page is hopelessly outdated for anyone working with the Tomcat 6 branch. We need to figure out the best way to document security measures for the different supported branches. Ken 10:25, 20 March 2009 (UTC)

I've not had call to use Tomcat 6, but in a few months I plan to start experimenting with the embedded version. I don't mind expanding the article to have a section on 6 (and keep the section on 5.5), but I can't contribute anything just yet. My preference would be a single article as it will cut down on duplication. In the meantime, any differences, areas to cover, new features, etc. that others could note down will help speed things up. Darren 09:11, 26 March 2009 (UTC)

HttpOnly configuration

Tomcat versions from 5.5.28 and 6.0.19 support the HttpOnly [1] cookie option.

This is configured in the conf/context.xml file:

<Context useHttpOnly="true">
...
</Context>

Simon Bennetts 14:40, 18 June 2010 (UTC)

Overriding Tomcat Version Number

Rebuilding the catalina.jar to alter ServerInfo.properties may not be an ideal way to override the version number, the same effect can be achieved without repackaging JARs in the default distribution (repackaging can be somewhat intrusive and/or impractical). Classloader classpaths can be patched using strategically placed files on the classpath. Classes that are loaded first always take precedence, the same goes for properties files, hence you can override by creating files in the following places:

# For Tomcat 5.5 (inject your new file onto the path of the server classloader):
${catalina.home}/server/classes/org/apache/catalina/util/ServerInfo.properties
# For Tomcat 6 (inject it onto the path of the common classloader, or whichever classloader is loading catalina.jar):
${catalina.home}/lib/org/apache/catalina/util/ServerInfo.properties

In both cases, ${catalina.home} is typically either the root of your local installation, or your global installation if you are making use of disjoint installs using ${catalina.base} to provide instance-specific information.

autoDeploy feature

Wouldn't it make sense to disable the autoDeploy feature in production environments for added security?

Pierre Ernst 2011-08-12

Disabling weak ciphers in Tomcat

Copied from [2]

In order to disable weak ciphers, please modify your SSL Connector container attribute inside server.xml with the following information.

ciphers="SSL_RSA_WITH_RC4_128_SHA, TLS_RSA_WITH_AES_128_CBC_SHA, 
 TLS_DHE_RSA_WITH_AES_128_CBC_SHA, TLS_DHE_DSS_WITH_AES_128_CBC_SHA, 
 SSL_RSA_WITH_3DES_EDE_CBC_SHA, SSL_DHE_RSA_WITH_3DES_EDE_CBC_SHA, 
 SSL_DHE_DSS_WITH_3DES_EDE_CBC_SHA"

Example:

<Connector port="443" maxHttpHeaderSize="8192" address="192.168.1.1"
enableLookups="false" disableUploadTimeout="true"
acceptCount="100" scheme="https" secure="true"
clientAuth="false" sslProtocol="SSL"
ciphers="SSL_RSA_WITH_RC4_128_SHA, TLS_RSA_WITH_AES_128_CBC_SHA, 
 TLS_DHE_RSA_WITH_AES_128_CBC_SHA, TLS_DHE_DSS_WITH_AES_128_CBC_SHA, 
 SSL_RSA_WITH_3DES_EDE_CBC_SHA, SSL_DHE_RSA_WITH_3DES_EDE_CBC_SHA,   
 SSL_DHE_DSS_WITH_3DES_EDE_CBC_SHA
keystoreFile="SomeDir/SomeFile.key" keystorePass="Poodle"
truststoreFile="SomeDir/SomeFile.truststore" truststorePass="HomeRun"/>

User:Psiinon 2011-10-06

User:Dirk Wetter 2014-03-27 : Those ciphers were maybe ok in 2011, in 2014 I would not recommend using RC4 and CBC ciphers!

No missing steps required in Tomcat 7 or 8

I've done some research and as far as I can tell there are no recommended hardening steps for Tomcat 7 or 8 missing from this guide.

http://tomcat.apache.org/tomcat-7.0-doc/security-howto.html#Securing_Management_Applications http://chandank.com/application-server/tomcat/apache-tomcat-hardening-and-security-guide

The SSL Cipher list should be upgraded however: http://www.sslshopper.com/article-how-to-disable-weak-ciphers-and-ssl-2-in-tomcat.html

Kenneth Kron (talk) 16:56, 22 August 2014 (CDT)