CWE-338

Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)

Base

Draft

Description

The product uses a Pseudo-Random Number Generator (PRNG) in a security context, but the PRNG's algorithm is not cryptographically strong.

{"xhtml:p":["When a non-cryptographic PRNG is used in a cryptographic context, it can expose the cryptography to certain types of attacks.","Often a pseudo-random number generator (PRNG) is not designed for cryptography. Sometimes a mediocre source of randomness is sufficient or preferable for algorithms that use random numbers. Weak generators generally take less processing power and/or do not use the precious, finite, entropy sources on a system. While such PRNGs might have very useful features, these same features could be used to break the cryptography."]}

Parent Weaknesses (ChildOf)

CWE-330: Use of Insufficiently Random V...

Common Consequences

Scope

Access Control

Impact

Bypass Protection Mechanism

Potential Mitigations

Implementation

Use functions or hardware which use a hardware-based random number generation for all crypto. This is the recommended solution. Use CyptGenRandom on Windows, or hw_rand() on Linux.

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