CVE-2026-64311 crypto: loongson - Remove broken and unused loongson-rng

What is CVE-2026-64311?

CVE-2026-64311 is a high-severity use after free vulnerability in Linux kernel, published on 25 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

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/[email protected] and https://lore.kernel.org/r/[email protected]

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.

Weakness: CWE-416

Which versions are affected by CVE-2026-64311?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-64311?

Apply the vendor's patch.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2026-64311 being exploited?

There is no known exploitation of CVE-2026-64311 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2026-64311, DEBIAN-CVE-2026-64311, GHSA-x266-xjm8-j78q, ROOT-OS-UBUNTU-2204-CVE-2026-64311, UBUNTU-CVE-2026-64311.