CVE-2025-7394: wolfssl

Vulnerability summary

CVE-2025-7394 is a critical (CVSS 9.8) vulnerability in wolfssl. EPSS estimates a 0.46% chance of exploitation in the next 30 days, higher than 39.7% of scored vulnerabilities.

Timeline

1. 18-07-2025
   PublishedVulnerability first disclosed.
2. 21-07-2025
   Last modifiedVulnerability information updated.

Description

In the OpenSSL compatibility layer implementation, the function RAND_poll() was not behaving as expected and leading to the potential for predictable values returned from RAND_bytes() after fork() is called. This can lead to weak or predictable random numbers generated in applications that are both using RAND_bytes() and doing fork() operations. This only affects applications explicitly calling RAND_bytes() after fork() and does not affect any internal TLS operations. Although RAND_bytes() documentation in OpenSSL calls out not being safe for use with fork() without first calling RAND_poll(), an additional code change was also made in wolfSSL to make RAND_bytes() behave similar to OpenSSL after a fork() call without calling RAND_poll(). Now the Hash-DRBG used gets reseeded after detecting running in a new process. If making use of RAND_bytes() and calling fork() we recommend updating to the latest version of wolfSSL. Thanks to Per Allansson from Appgate for the report.

• CWE-200Exposure of Sensitive Information to an Unauthorized ActorThe product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.
• CWE-338Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)The product uses a Pseudo-Random Number Generator (PRNG) in a security context, but the PRNG's algorithm is not cryptographically strong.