CVE-2026-99244: Linux kernel · pid_namespace: prevent TIF_NOTIFY_SIGNAL from interrupting the reaper
Source GCVE Database
Not known to be exploited · fixed in f46cd8241d9b83f2279cc0db3e9d3e181b548a59 : update Linux kernel when convenient.
Data as of 3 Nov 2026, 13:28 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
A fix has been implemented in the Linux kernel to address this issue by adding a no_notify_signal guard that prevents TIF_NOTIFY_SIGNAL from interrupting the reaper. Users should apply the updated kernel version containing this fix once available.
Description
A vulnerability in the Linux kernel's pid_namespace handling allows the TIF_NOTIFY_SIGNAL flag to interrupt the reaper process improperly. The issue arises because the TIF_NOTIFY_SIGNAL flag can be set again after being cleared, causing the reaper to busy-wait or return prematurely from sleep calls. The fix introduces a no_notify_signal guard to ensure the reaper sleeps correctly until a child process exits or is freed.
References
- nvd.nist.gov/vuln/detail/CVE-2026-99244 (opens in a new tab)
- git.kernel.org/stable/c/2c20ace1698d03a23467351be1d281e89b36ade3 (opens in a new tab)
- git.kernel.org/stable/c/30b274508c743f243c82904954c4e416d7143d4c (opens in a new tab)
- git.kernel.org/stable/c/3d15ac36ce174477efa5365e424dbd47950fd2b9 (opens in a new tab)
- git.kernel.org/stable/c/70178691c467c8f9f722765299fd8524c3121a35 (opens in a new tab)
- git.kernel.org/stable/c/9ab0324f4868eeb20c63f063a1e5bc01d5539212 (opens in a new tab)
- git.kernel.org/stable/c/f46cd8241d9b83f2279cc0db3e9d3e181b548a59 (opens in a new tab)