OWASP - User contributions [en]

Insufficient Entropy

2007-02-12T21:09:04Z

Wvande: /* Categories */

{{Template:Vulnerability}}

==Description==

When an undesirably low amount of [[entropy]] is available. Psuedo Random Number Generators are susceptible to suffering from insufficient entropy when they are initialized because entropy data may not be available to them yet.

==Examples ==

==Related Threats==

In many cases a PRNG uses a combination of the system clock and entropy to create seed data. In the case where insufficient entropy is available, an attacker can reduce the size magnitude of the seed value considerably. Furthermore, by guessing values of the system clock, they can create a manageable set of possible PRNG outputs.

==Related Attacks==

==Related Vulnerabilities==

==Related Countermeasures==

Many PRNG's (/dev/random and /dev/urandom for example) store their last value before shutdown. By using this value at intialization, they can sometimes avoid insufficient or predictable starting entropy.

==Categories==
[[:Category:Cryptography]]

[[:Category:Cryptographic Vulnerability]]

{{Template:Stub}}

Insufficient Entropy

2007-02-12T21:08:20Z

Wvande: /* Related Countermeasures */

{{Template:Vulnerability}}

==Description==

When an undesirably low amount of [[entropy]] is available. Psuedo Random Number Generators are susceptible to suffering from insufficient entropy when they are initialized because entropy data may not be available to them yet.

==Examples ==

==Related Threats==

In many cases a PRNG uses a combination of the system clock and entropy to create seed data. In the case where insufficient entropy is available, an attacker can reduce the size magnitude of the seed value considerably. Furthermore, by guessing values of the system clock, they can create a manageable set of possible PRNG outputs.

==Related Attacks==

==Related Vulnerabilities==

==Related Countermeasures==

Many PRNG's (/dev/random and /dev/urandom for example) store their last value before shutdown. By using this value at intialization, they can sometimes avoid insufficient or predictable starting entropy.

==Categories==

{{Template:Stub}}

[[Category:Cryptographic Vulnerability]]

Insufficient Entropy

2007-02-12T21:06:42Z

Wvande: /* Related Countermeasures */

{{Template:Vulnerability}}

==Description==

When an undesirably low amount of [[entropy]] is available. Psuedo Random Number Generators are susceptible to suffering from insufficient entropy when they are initialized because entropy data may not be available to them yet.

==Examples ==

==Related Threats==

In many cases a PRNG uses a combination of the system clock and entropy to create seed data. In the case where insufficient entropy is available, an attacker can reduce the size magnitude of the seed value considerably. Furthermore, by guessing values of the system clock, they can create a manageable set of possible PRNG outputs.

==Related Attacks==

==Related Vulnerabilities==

==Related Countermeasures==

Many PRNG's (/dev/random and /dev/urandom for example) store their last value before shutdown. By using this value at intialization, they can sometimes avoid insufficient or predictable starting entropy.

[[:Category:Cryptography]]

==Categories==

{{Template:Stub}}

[[Category:Cryptographic Vulnerability]]

Insufficient Entropy

2007-02-12T21:03:42Z

Wvande: /* Description */ added entropy link

{{Template:Vulnerability}}

==Description==

When an undesirably low amount of [[entropy]] is available. Psuedo Random Number Generators are susceptible to suffering from insufficient entropy when they are initialized because entropy data may not be available to them yet.

==Examples ==

==Related Threats==

In many cases a PRNG uses a combination of the system clock and entropy to create seed data. In the case where insufficient entropy is available, an attacker can reduce the size magnitude of the seed value considerably. Furthermore, by guessing values of the system clock, they can create a manageable set of possible PRNG outputs.

==Related Attacks==

==Related Vulnerabilities==

==Related Countermeasures==

[[:Category:Cryptography]]

==Categories==

{{Template:Stub}}

[[Category:Cryptographic Vulnerability]]

Insufficient Entropy

2007-02-12T20:59:38Z

Wvande: /* Related Threats */

{{Template:Vulnerability}}

==Description==

When an undesirably low amount of random data is available. Psuedo Random Number Generators are susceptible to suffering from insufficient entropy when they are initialized because random data may not be available to them yet.

==Examples ==

==Related Threats==

In many cases a PRNG uses a combination of the system clock and entropy to create seed data. In the case where insufficient entropy is available, an attacker can reduce the size magnitude of the seed value considerably. Furthermore, by guessing values of the system clock, they can create a manageable set of possible PRNG outputs.

==Related Attacks==

==Related Vulnerabilities==

==Related Countermeasures==

[[:Category:Cryptography]]

==Categories==

{{Template:Stub}}

[[Category:Cryptographic Vulnerability]]

Insufficient Entropy

2007-02-12T20:50:18Z

Wvande: /* Description */ added basic definition

PRNG direct cryptanalytic attack

2007-02-12T13:24:47Z

Wvande: /* Description */ added examples sub heading

== Description ==

A category of PRNG attacks in which an attacker is directly able to distinguish between PRNG outputs and random outputs. [http://www.schneier.com/paper-prngs.pdf]

== Examples ==

----

{{Template:Stub}}
{{Template:Attack}

PRNG direct cryptanalytic attack

2007-02-12T13:24:01Z

Wvande: /* Description */

PRNG direct cryptanalytic attack

2007-02-12T13:23:46Z

Wvande:

PRNG permanent compromise attack

2007-02-12T03:23:39Z

Wvande: /* Examples */

== Description ==

A type of [[PRNG state compromise extension attack]] in which an attacker compromises the state of the PRNG at some arbitrary time t. From t, all future and past states of the PRNG become vulnerable to attack [http://www.schneier.com/paper-prngs.pdf].

== Examples ==

In 1999, Reliable Software Technologies was able to crack the card shuffling algorithm used in an online Texas Hold 'Em card game (using software developed by ASF Software Inc.). By identifying the seed value used by ASF's PRNG algorithm, Reliable was able to identify how the cards would be shuffled and, hence, the contents of the deck [http://www.developer.com/tech/article.php/10923_616221_1?o=0].

----

{{Template:Stub}}
{{Template:Attack}}

PRNG permanent compromise attack

2007-02-12T03:20:01Z

Wvande: /* Description */

== Description ==

A type of [[PRNG state compromise extension attack]] in which an attacker compromises the state of the PRNG at some arbitrary time t. From t, all future and past states of the PRNG become vulnerable to attack [http://www.schneier.com/paper-prngs.pdf].

== Examples ==

In 1999, Reliable Software Technologies was able to crack the card shuffling algorithm used in an online Texas Hold 'Em card game (developed by ASF Software). By identifying the seed value used by ASF's PRNG algorithm, Reliable was able to identify how the cards would be shuffled and, hence, the contents of the deck [http://www.developer.com/tech/article.php/10923_616221_1?o=0].

----

{{Template:Stub}}
{{Template:Attack}}

PRNG permanent compromise attack

2007-02-12T02:51:23Z

Wvande: /* Description */

PRNG permanent compromise attack

2007-02-12T02:48:42Z

Wvande: /* Description */

== Description ==

A type of [[PRNG State Compromise Extension Attack]] in which an attacker compromises the state of the PRNG at some arbitrary time t. From t, all future and past states of the PRNG become vulnerable to attack [http://www.schneier.com/paper-prngs.pdf].

----

{{Template:Stub}}
{{Template:Attack}}

PRNG state compromise extension attack

2007-02-12T02:45:43Z

Wvande:

== Description ==

A category of attacks in which an attacker compromises a single state of the PRNG and penetrates past or future outputs of the PRNG using this information [http://www.schneier.com/paper-prngs.pdf]. Usually this attack is executed using the seed state or a vulnerable state in which insufficient entropy is available.

----

{{Template:Stub}}
{{Template:Attack}

PRNG permanent compromise attack

2007-02-12T02:36:04Z

Wvande: /* Description */

== Description ==

A type of PRNG State Compromise Extension Attack in which an attacker compromises the state of the PRNG at some arbitrary time t. From t, all future and past states of the PRNG become vulnerable to attack [http://www.schneier.com/paper-prngs.pdf].

----

{{Template:Stub}}
{{Template:Attack}}

PRNG permanent compromise attack

2007-02-12T02:34:52Z

Wvande: /* Description */

PRNG permanent compromise attack

2007-02-12T02:23:27Z

Wvande: /* Description */

==Description==

{{Template:Stub}}
{{Template:Attack}}

PRNG permanent compromise attack

2007-02-12T02:22:38Z

Wvande:

==Description==

{{Template:Stub}}
{{Template:Attack}}

PRNG permanent compromise attack

2007-02-12T02:20:34Z

Wvande:

PRNG Seed Error

2007-02-12T02:04:45Z

Wvande: /* Related Threats */

{{Template:Vulnerability}}

==Description==
The incorrect use of a seed by a Psuedo Random Number Generator [http://cve.mitre.org/docs/plover/SECTION.9.20.html#RAND.SEED] . A seed error is usually brought on through the erroneous generation or application of a seed state.

==Examples ==

==Related Threats==
The application of a seed state that is known to an attacker can lead to a permanent compromise attack [http://www.schneier.com/paper-prngs.html].

==Related Attacks==

==Related Vulnerabilities==

==Related Countermeasures==

==Categories==

{{Template:Stub}}

[[Category:Cryptographic Vulnerability]]

PRNG Seed Error

2007-02-12T01:57:56Z

Wvande: /* Description */

{{Template:Vulnerability}}

==Description==
The incorrect use of a seed by a Psuedo Random Number Generator [http://cve.mitre.org/docs/plover/SECTION.9.20.html#RAND.SEED] . A seed error is usually brought on through the erroneous generation or application of a seed state.

==Examples ==

==Related Threats==

==Related Attacks==

==Related Vulnerabilities==

==Related Countermeasures==

==Categories==

{{Template:Stub}}

[[Category:Cryptographic Vulnerability]]

PRNG Seed Error

2007-02-12T01:56:06Z

Wvande: /* Description */ - basic definition of PRNG seed error

{{Template:Vulnerability}}

==Description==
The incorrect use of a seed. [http://cve.mitre.org/docs/plover/SECTION.9.20.html#RAND.SEED] . A seed error is usually brought on by through erroneous generation or application of a seed state.

==Examples ==

==Related Threats==

==Related Attacks==

==Related Vulnerabilities==

==Related Countermeasures==

==Categories==

{{Template:Stub}}

[[Category:Cryptographic Vulnerability]]