CVE-2026-99244: Linux kernel · pid_namespace: prevent TIF_NOTIFY_SIGNAL from interrupting the reaper
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in f46cd8241d9b83f2279cc0db3e9d3e181b548a59 : update Linux kernel when convenient.
Data as of 3 Nov 2026, 11:43 UTC
Rated Medium by Threat Radar's AI analysis · CVSS not yet scored by NVD
Thin evidence
One scorer or none- Patch
- Available – fixed in f46cd8241d9b83f2279cc0db3e9d3e181b548a59, 70178691c467c8f9f722765299fd8524c3121a35, 30b274508c743f243c82904954c4e416d7143d4c +8
Exploitation evidence
Disclosed: evidence found.
CVE published 3 Nov 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
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in– |
AI-suggested
This vulnerability has been fixed in Linux kernel versions 6.10, 6.6.161, 6.1.191, 5.16, and 5.11, among others. Users and administrators should upgrade to these fixed versions or later to remediate the issue. No additional mitigation is required beyond applying the official patches.
Description
A vulnerability in the Linux kernel's pid_namespace subsystem allows the TIF_NOTIFY_SIGNAL flag to interrupt the reaper process improperly. This issue arises because the flag can be set repeatedly during livepatch operations, causing the reaper to busy-wait or return prematurely from sleep calls. The flaw has been addressed by introducing a no_notify_signal guard that prevents signal_pending() from being affected by TIF_NOTIFY_SIGNAL, ensuring the reaper sleeps correctly until child processes exit or are freed.
References
- git.kernel.org/stable/c/2c20ace1698d03a23467351be1d281e89b36ade3 (opens in a new tab)
- git.kernel.org/stable/c/9ab0324f4868eeb20c63f063a1e5bc01d5539212 (opens in a new tab)
- git.kernel.org/stable/c/30b274508c743f243c82904954c4e416d7143d4c (opens in a new tab)
- git.kernel.org/stable/c/70178691c467c8f9f722765299fd8524c3121a35 (opens in a new tab)
- git.kernel.org/stable/c/3d15ac36ce174477efa5365e424dbd47950fd2b9 (opens in a new tab)
- git.kernel.org/stable/c/f46cd8241d9b83f2279cc0db3e9d3e181b548a59 (opens in a new tab)