CVE-2026-74740: Linux kernel · net/sched: act_api: fix TOCTOU NULL deref on a->goto_chain
Source GCVE Database
Not known to be exploited · fixed in f60b396ee174206fe08ebf997d16cd3801b77b22 : update Linux kernel when convenient.
Data as of 30 Oct 2026, 19:33 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 f60b396ee174206fe08ebf997d16cd3801b77b22, abceabc4408fca6a9dd52611f5d197dec9390d63, 91d55fd1fdb85c8371ca8793c788ea7d5192383a +3
Exploitation evidence
Disclosed: evidence found.
CVE published 26 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 has been implemented that consolidates the pointer read and check into a single operation, eliminating the race condition. Users should apply the official kernel update containing this fix once available. No other mitigation steps are indicated.
Description
A time-of-check to time-of-use (TOCTOU) race condition in the Linux kernel's net/sched act_api component could lead to a NULL pointer dereference. The issue arises from separate reads of a pointer that may be cleared concurrently, causing a NULL dereference in tcf_action_goto_chain_exec(). The flaw has been fixed by consolidating the pointer read and check into a single operation.
References
- nvd.nist.gov/vuln/detail/CVE-2026-74740 (opens in a new tab)
- git.kernel.org/stable/c/1ec48b6715c29b20105e3485206602cff6c51ae5 (opens in a new tab)
- git.kernel.org/stable/c/28aa0c9dd0b1b38436995d4c15621ad3f896c7e3 (opens in a new tab)
- git.kernel.org/stable/c/6b70886ebc428eed43a069c8944a931b5fb3f4e4 (opens in a new tab)
- git.kernel.org/stable/c/91d55fd1fdb85c8371ca8793c788ea7d5192383a (opens in a new tab)
- git.kernel.org/stable/c/abceabc4408fca6a9dd52611f5d197dec9390d63 (opens in a new tab)
- git.kernel.org/stable/c/f60b396ee174206fe08ebf997d16cd3801b77b22 (opens in a new tab)