VulnerabilityPublished 28 Oct 2026

CVE-2026-99169: Linux kernel · futex: Fix mm reuse handling for FUT_OFF_MMSHARED

Affects Linux kernelSource CVE Database V5

Not known to be exploited · fixed in c17cc2027773e8e4913c5ab0fe3a489b1ed5bf81 : update Linux kernel when convenient.

Data as of 28 Oct 2026, 10:58 UTC

Severity

Unrated

Rated by Threat Radar · CVSS not yet scored by NVD

Patch: Available – fixed in c17cc2027773e8e4913c5ab0fe3a489b1ed5bf81, 3267512ad1c2cc0c7768c5b014dc2cceb398a801, 2855ddc6844f527e375e78afb55ec2a5182f23b3

Exploitation evidence

Disclosed: evidence found.
CVE published 28 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade Linux kernel to c17cc2027773e8e4913c5ab0fe3a489b1ed5bf81, 3267512ad1c2cc0c7768c5b014dc2cceb398a801 or 2855ddc6844f527e375e78afb55ec2a5182f23b3.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ 222993395ed38f3751287f4bd82ef46b3eb3a66d, < c17cc2027773e8e4913c5ab0fe3a489b1ed5bf81	Fixed in c17cc2027773e8e4913c5ab0fe3a489b1ed5bf81
LinuxLinux	Affected ≥ 222993395ed38f3751287f4bd82ef46b3eb3a66d, < 3267512ad1c2cc0c7768c5b014dc2cceb398a801	Fixed in 3267512ad1c2cc0c7768c5b014dc2cceb398a801
LinuxLinux	Affected ≥ 222993395ed38f3751287f4bd82ef46b3eb3a66d, < 2855ddc6844f527e375e78afb55ec2a5182f23b3	Fixed in 2855ddc6844f527e375e78afb55ec2a5182f23b3
LinuxLinux	Affected =5.7	Fixed in–

Description

In the Linux kernel, the following vulnerability has been resolved: futex: Fix mm reuse handling for FUT_OFF_MMSHARED A FUT_OFF_MMSHARED futex is a shared futex that refers to an MM. It is possible for a process to wait on a shared futex with a different MM because a FUT_OFF_INODE waiter can be requeued onto a FUT_OFF_MMSHARED futex by another process. This can cause FUT_OFF_MMSHARED waiters on a freed MM to consume wakeups intended for a newly allocated MM at the same address. Fix it by keying FUT_OFF_MMSHARED using a unique 64-bit per-MM ID. Leave private futexes as before to avoid influencing the performance of the hotpath. (Multi-threaded processes typically implicitly use FUT_OFF_MMSHARED by setting clear_child_tid such that it points into anonymous memory, which causes mm_release() in a multi-threaded mm to perform FUTEX_WAKE.)

References

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