CVE-2026-64477: Linux kernel · x86,fs/resctrl: Prevent out-of-bounds access while offlining CPU when SNC enabled
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 3 Nov 2026, 19:29 UTC
Rated Medium by Threat Radar's AI analysis · No CVSS score from NVD or the CNA
Thin evidence
One scorer or noneExploitation evidence
Disclosed: evidence found.
CVE published 25 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 3 Nov 2026.
What to do
AI-suggested
A fix has been implemented in the Linux kernel by refactoring the limbo handler and adding safety checks in the RMID reader to prevent out-of-bounds access. Users should apply the official kernel updates containing this fix once available. No additional mitigation steps are indicated.
Description
A vulnerability in the Linux kernel's x86 resctrl filesystem can cause out-of-bounds memory access when offlining a CPU with SNC (Sub-NUMA Clustering) enabled. This occurs because the system queries an empty CPU mask leading to invalid NUMA node ID lookups. The issue is addressed by refactoring the limbo handler to avoid unnecessary RMID reads and adding safety checks in the RMID reader.
References
- git.kernel.org/stable/c/ebc300b7ee0c669fa76a7a8858298ff32e296103 (opens in a new tab)
- git.kernel.org/stable/c/be1567992417dc92133e74126de7a6066c825ac9 (opens in a new tab)
- git.kernel.org/stable/c/58c5ec23b1a238eb75cb0aba6f69d8f9e68ef0b2 (opens in a new tab)
- git.kernel.org/stable/c/fc16126cc11d9f507130bf84ab137ee0938c900e (opens in a new tab)