CVE-2026-74740net/sched: act_api: fix TOCTOU NULL deref on a->goto_chain
- —Not scoredno CVSS score yet
- 0.18%Exploitation in 30 daysEPSS · top 92% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: net/sched: act_api: fix TOCTOU NULL deref on a->goto_chain tcf_action_exec() handles TC_ACT_GOTO_CHAIN by first checking rcu_access_pointer(a->goto_chain) and then calling tcf_action_goto_chain_exec(), which does a second, independent rcu_dereference_bh(a->goto_chain) read and immediately dereferences chain->filter_chain. A concurrent tcf_action_set_ctrlact() (e.g. the gact replace path) can clear a->goto_chain between the two reads, so the second read returns NULL and tcf_action_goto_chain_exec() dereferences NULL. Fix the race by doing a single rcu_dereference_bh() read of a->goto_chain in tcf_action_exec(), checking it once for NULL, and passing the resulting chain pointer into tcf_action_goto_chain_exec(). This turns the split check/use into a single check/use on one value.
Timeline
ID reserved
By Linux
- 11 days later
· 11 days later
Published
- 2 months later
· 2 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
No CVSS score yet: neither the CNA, CISA nor NVD has scored this CVE. NVD status: Received.
- EPSS (exploitation in 30 days)
- 0.18% · top 92% of all CVEs (12 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Not scored.
Affected products
- affected ee3bbfe806cdb46b02cda63626cb50a7a7b19fc5 – < 28aa0c9dd0b1b38436995d4c15621ad3f896c7e3
- affected ee3bbfe806cdb46b02cda63626cb50a7a7b19fc5 – < 91d55fd1fdb85c8371ca8793c788ea7d5192383a
- affected ee3bbfe806cdb46b02cda63626cb50a7a7b19fc5 – < 1ec48b6715c29b20105e3485206602cff6c51ae5
- affected ee3bbfe806cdb46b02cda63626cb50a7a7b19fc5 – < abceabc4408fca6a9dd52611f5d197dec9390d63
- affected ee3bbfe806cdb46b02cda63626cb50a7a7b19fc5 – < 6b70886ebc428eed43a069c8944a931b5fb3f4e4
- affected ee3bbfe806cdb46b02cda63626cb50a7a7b19fc5 – < f60b396ee174206fe08ebf997d16cd3801b77b22
- affected 5.1
- unaffected < 5.1
- unaffected 6.1.191 – ≤ 6.1.*
- unaffected 6.6.153 – ≤ 6.6.*
- unaffected 6.12.105 – ≤ 6.12.*
- unaffected 6.18.46 – ≤ 6.18.*
- unaffected 7.1.10 – ≤ 7.1.*
- unaffected 7.2 – ≤ *
References
References6
- https://git.kernel.org/stable/c/28aa0c9dd0b1b38436995d4c15621ad3f896c7e3 (opens in a new tab)
- https://git.kernel.org/stable/c/91d55fd1fdb85c8371ca8793c788ea7d5192383a (opens in a new tab)
- https://git.kernel.org/stable/c/1ec48b6715c29b20105e3485206602cff6c51ae5 (opens in a new tab)
- https://git.kernel.org/stable/c/abceabc4408fca6a9dd52611f5d197dec9390d63 (opens in a new tab)
- https://git.kernel.org/stable/c/6b70886ebc428eed43a069c8944a931b5fb3f4e4 (opens in a new tab)
- https://git.kernel.org/stable/c/f60b396ee174206fe08ebf997d16cd3801b77b22 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-66570 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-74740)Record last updated .