CVE-2026-74391: Linux kernel · tracing: Bound synthetic-field strings with seq_buf
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in f07883450eb14d1cf020b55d9f3a7ec5683bcd26 : update Linux kernel when convenient.
Data as of 30 Oct 2026, 13:20 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 f07883450eb14d1cf020b55d9f3a7ec5683bcd26, cf334620036ad2250e008c7e7bb6646a3938b7b0, baa333b2700a7fa3529d504529c8c10060fd687c +3
Exploitation evidence
Disclosed: evidence found.
CVE published 15 Aug 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 30 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
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
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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AI-suggested
A fix is available and has been applied in the Linux kernel. Users should update to a fixed kernel version that includes the patch identified by the provided commit hashes. No additional mitigation is required beyond applying the official fix.
Description
A vulnerability in the Linux kernel tracing subsystem was addressed by bounding synthetic-field strings using seq_buf. Previously, synthetic field helpers used raw strcat() to append strings in fixed-size buffers, which could lead to buffer overflows when handling long key lists, field names, or saved filters. The fix replaces strcat() with seq_buf-based string construction and returns an error if the buffer size limit is exceeded, preventing overflow.
References
- git.kernel.org/stable/c/9f8ef2e1e95a42044e614b0a5277e3f53f545135 (opens in a new tab)
- git.kernel.org/stable/c/0c584c27f6649a93ec12061cc779a4bd8f7c1434 (opens in a new tab)
- git.kernel.org/stable/c/88b901fdc1662b131ff908cbd017333b61e7acc8 (opens in a new tab)
- git.kernel.org/stable/c/baa333b2700a7fa3529d504529c8c10060fd687c (opens in a new tab)
- git.kernel.org/stable/c/cf334620036ad2250e008c7e7bb6646a3938b7b0 (opens in a new tab)
- git.kernel.org/stable/c/f07883450eb14d1cf020b55d9f3a7ec5683bcd26 (opens in a new tab)