CVE-2025-7394 Weak cryptography in wolfSSL
Predictable random numbers in wolfSSL after fork() allow attackers to compromise cryptographic keys or session tokens.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2025-7394?
CVE-2025-7394 is a high-severity vulnerability in Wolfssl Wolfssl, published on 18 Jul 2025. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official 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.
Which versions are affected by CVE-2025-7394?
It affects 1 product.
Products include Wolfssl Wolfssl.
How do I fix CVE-2025-7394?
Upgrade to a fixed version.
Is CVE-2025-7394 being exploited?
There is no known exploitation of CVE-2025-7394 in the wild and no public exploit code.
Other vulnerabilities in Wolfssl Wolfssl
Sources
Also known as DEBIAN-CVE-2025-7394, GHSA-jgh6-fqf6-cpj8, JLSEC-2026-689, UBUNTU-CVE-2025-7394.