CVE-2026-99237: Linux kernel · tracing: Hold trace_types_lock when resetting last boot data from readers
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 7.8 High · fixed in d6d991afe775ab7fcf89523a2502b7ca3be56ffd : patch Linux kernel soon.
Data as of 2 Nov 2026, 16:30 UTC
Thin evidence
One scorer or none| CNA (Linux) | CVSS 3.1 | 7.8 |
|---|
- Patch
- Available – fixed in d6d991afe775ab7fcf89523a2502b7ca3be56ffd, 92b69f6db640dadc0851762ee2e12db99f083cad, 1f06cfe0b60a878619d1d8efe1cd0f515b7dc2aa
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 2 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 2 Nov 2026.
What to do
Upgrade Linux kernel to d6d991afe775ab7fcf89523a2502b7ca3be56ffd, 92b69f6db640dadc0851762ee2e12db99f083cad or 1f06cfe0b60a878619d1d8efe1cd0f515b7dc2aa.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in– |
AI-suggested
A fix is available and has been applied in the Linux kernel. Users and administrators should update to the fixed versions identified by the commits d6d991afe775ab7fcf89523a2502b7ca3be56ffd, 92b69f6db640dadc0851762ee2e12db99f083cad, and 1f06cfe0b60a878619d1d8efe1cd0f515b7dc2aa. No additional mitigation is required once the update is applied.
Description
CVE-2026-99237 is a high-severity vulnerability in the Linux kernel tracing subsystem. It involves improper locking when resetting last boot data from readers, which can lead to double freeing of memory and concurrent modification issues. The flaw arises because trace_types_lock was not held in certain code paths, allowing race conditions between readers and module notifiers. This vulnerability has been fixed by ensuring trace_types_lock is held appropriately during these operations.