{"cve":"CVE-2026-74740","nvd":{"published":"2026-08-26T15:16:52.743","modified":"2026-10-30T13:20:05.597","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: act_api: fix TOCTOU NULL deref on a->goto_chain\n\ntcf_action_exec() handles TC_ACT_GOTO_CHAIN by first checking\nrcu_access_pointer(a->goto_chain) and then calling\ntcf_action_goto_chain_exec(), which does a second, independent\nrcu_dereference_bh(a->goto_chain) read and immediately dereferences\nchain->filter_chain. A concurrent tcf_action_set_ctrlact() (e.g. the gact\nreplace path) can clear a->goto_chain between the two reads, so the second\nread returns NULL and tcf_action_goto_chain_exec() dereferences NULL.\n\nFix the race by doing a single rcu_dereference_bh() read of a->goto_chain\nin tcf_action_exec(), checking it once for NULL, and passing the resulting\nchain pointer into tcf_action_goto_chain_exec(). This turns the split\ncheck/use into a single check/use on one value.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/1ec48b6715c29b20105e3485206602cff6c51ae5","https://git.kernel.org/stable/c/28aa0c9dd0b1b38436995d4c15621ad3f896c7e3","https://git.kernel.org/stable/c/6b70886ebc428eed43a069c8944a931b5fb3f4e4","https://git.kernel.org/stable/c/91d55fd1fdb85c8371ca8793c788ea7d5192383a","https://git.kernel.org/stable/c/abceabc4408fca6a9dd52611f5d197dec9390d63"],"products":[],"source":"nvd","synced_at":"2026-10-30T13:47:47.119061695+00:00"},"epss":{"cve":"CVE-2026-74740","score":0.00175,"percentile":0.07061,"date":"2026-10-30"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}