Use-After-Free in Linux kernel (CVE-2026-64311)
Summary
Vulnerability in Linux kernel (CVE-2026-64311). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
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.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-64311 has been found in Linux kernel.
Successful exploitation can lead to full system takeover. CVSS score: 7.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2026-64311" on the vendor's site.
CVE-2026-64311 (Linux kernel) — CWE-416 / CVSS v3 7.8
Attack vector: local / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Use-after-free (CWE-416) exists in Linux kernel.
Check the vendor advisory for the affected versions of Linux kernel.
Severity: High (CVSS 7.8/10). Successful exploitation can lead to full system takeover.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Linux kernel を使っているサービスとバージョンを洗い出す。
-
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- BellSoft Alpaquita BELL-CVE-2026-64311 linux-lts Fixed in: 6.18.43-r0
- Ubuntu UBUNTU-CVE-2026-64311 linux-hwe-edge
References
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web nvd.nist.gov
- web github.com