Use After Free in Linux
CVE-2026-64311
In the Linux kernel, the following vulnerability has been resolved: crypto: loongson - Remove broken and unused loongson-rng The loongson-rng rng_alg has several vulnerabilities, including not providing forward security, and a use-after-free bug due to the use of wait_for_completion_interruptible(). Meanwhile, the rng_alg framework doesn't really have any purpose in the first place other than to access the software algorithms crypto/drbg.c and crypto/jitterentropy.c. Hardware-specific rng_algs have no in-kernel user, and unlike hwrng there's no feed into the actual Linux RNG. As such, there's really no point to this code. There are of course other rng_alg drivers that are similarly unused, but they're similarly in the process of being phased out, e.g. https://lore.kernel.org/r/20260529193648.18172-1-ebiggers@kernel.org and https://lore.kernel.org/r/20260529220430.34135-1-ebiggers@kernel.org Given that, there's no point in fixing forward these vulnerabilities, and it makes much more sense to simply roll back the addition of this driver. If this platform provides TRNG (not PRNG) functionality, it could make sense to add a hwrng driver, but it would be quite different.
Vulnerability class: Use-After-Free
EPSS: 0.002 (5.2th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Linux — versions 7.2-rc1, 766b2d724c8df071031412eea902b566a0049c31, 7.2
- Linux Linux_kernel
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-64311?
- CVE-2026-64311 is a high-severity vulnerability in Linux, classified under Use After Free. CVSS score: 7.8/10. Published 2026-07-25.
- How severe is CVE-2026-64311?
- High severity. CVSS v3 base score is 7.8 out of 10.