CVE-2026-97921: Linux kernel · tracing: Free histogram the field rejected for a bad modifier
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in e787361bb6b0026ea3eb4d3fa7a304c7fcb99555 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 17:16 UTC
Rated Low by Threat Radar's AI analysis · CVSS not yet scored by NVD
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 11% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in e787361bb6b0026ea3eb4d3fa7a304c7fcb99555, b22dc0add7d72b8bd9cae3188db0dd65da1c8652, a2652fcf96b63e9da04951e4e58e6a0672df695d +5
Exploitation evidence
Disclosed: evidence found.
CVE published 25 Sep 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.
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 6.1.189, 6.4, and corresponding commits. Users and administrators should upgrade affected Linux kernel versions to these fixed releases or later to remediate the issue. No additional mitigation is required once patched.
Description
A vulnerability in the Linux kernel tracing subsystem allows memory leaks when a histogram trigger is written with a value or variable modifier that is not allowed. The flaw occurs because certain error paths skip freeing allocated fields, leading to unreferenced memory objects. This issue has been fixed in Linux kernel versions 6.1.189, 6.4, and later commits.
References
- git.kernel.org/stable/c/a2652fcf96b63e9da04951e4e58e6a0672df695d (opens in a new tab)
- git.kernel.org/stable/c/3d42fed18b2c5707b6332ebe87b789fd768eb01b (opens in a new tab)
- git.kernel.org/stable/c/e787361bb6b0026ea3eb4d3fa7a304c7fcb99555 (opens in a new tab)
- git.kernel.org/stable/c/b22dc0add7d72b8bd9cae3188db0dd65da1c8652 (opens in a new tab)
- git.kernel.org/stable/c/891c21f6d5673b2a519b536243bfc6dd2d35beb6 (opens in a new tab)
- git.kernel.org/stable/c/230234d12ce42ab04132a32c3a848f07a5d27a71 (opens in a new tab)