{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-23413","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-01-13T15:37:46.014Z","datePublished":"2026-04-02T11:40:54.384Z","dateUpdated":"2026-05-11T22:06:25.728Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-05-11T22:06:25.728Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nclsact: Fix use-after-free in init/destroy rollback asymmetry\n\nFix a use-after-free in the clsact qdisc upon init/destroy rollback asymmetry.\nThe latter is achieved by first fully initializing a clsact instance, and\nthen in a second step having a replacement failure for the new clsact qdisc\ninstance. clsact_init() initializes ingress first and then takes care of the\negress part. This can fail midway, for example, via tcf_block_get_ext(). Upon\nfailure, the kernel will trigger the clsact_destroy() callback.\n\nCommit 1cb6f0bae504 (\"bpf: Fix too early release of tcx_entry\") details the\nway how the transition is happening. If tcf_block_get_ext on the q->ingress_block\nends up failing, we took the tcx_miniq_inc reference count on the ingress\nside, but not yet on the egress side. clsact_destroy() tests whether the\n{ingress,egress}_entry was non-NULL. However, even in midway failure on the\nreplacement, both are in fact non-NULL with a valid egress_entry from the\nprevious clsact instance.\n\nWhat we really need to test for is whether the qdisc instance-specific ingress\nor egress side previously got initialized. This adds a small helper for checking\nthe miniq initialization called mini_qdisc_pair_inited, and utilizes that upon\nclsact_destroy() in order to fix the use-after-free scenario. Convert the\ningress_destroy() side as well so both are consistent to each other."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"}}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/net/sch_generic.h","net/sched/sch_ingress.c"],"versions":[{"version":"230bb13650b0f186f540500fd5f5f7096a822a2a","lessThan":"a73d95b57bf9faebdfed591bcb7ed9292062a84c","status":"affected","versionType":"git"},{"version":"1cb6f0bae50441f4b4b32a28315853b279c7404e","lessThan":"37bef86e5428d59f70a4da82b80f9a8f252fecbe","status":"affected","versionType":"git"},{"version":"1cb6f0bae50441f4b4b32a28315853b279c7404e","lessThan":"4c9af67f99aa3e51b522c54968ab3ac8272be41c","status":"affected","versionType":"git"},{"version":"1cb6f0bae50441f4b4b32a28315853b279c7404e","lessThan":"0509b762bc5e8ea7b8391130730c6d8502fc6e69","status":"affected","versionType":"git"},{"version":"1cb6f0bae50441f4b4b32a28315853b279c7404e","lessThan":"a0671125d4f55e1e98d9bde8a0b671941987e208","status":"affected","versionType":"git"},{"version":"f61ecf1bd5b562ebfd7d430ccb31619857e80857","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/net/sch_generic.h","net/sched/sch_ingress.c"],"versions":[{"version":"6.10","status":"affected"},{"version":"0","lessThan":"6.10","status":"unaffected","versionType":"semver"},{"version":"6.6.130","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.78","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.20","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"6.19.10","lessThanOrEqual":"6.19.*","status":"unaffected","versionType":"semver"},{"version":"7.0","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6.41","versionEndExcluding":"6.6.130"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10","versionEndExcluding":"6.12.78"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10","versionEndExcluding":"6.18.20"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10","versionEndExcluding":"6.19.10"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10","versionEndExcluding":"7.0"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.9.10"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/a73d95b57bf9faebdfed591bcb7ed9292062a84c"},{"url":"https://git.kernel.org/stable/c/37bef86e5428d59f70a4da82b80f9a8f252fecbe"},{"url":"https://git.kernel.org/stable/c/4c9af67f99aa3e51b522c54968ab3ac8272be41c"},{"url":"https://git.kernel.org/stable/c/0509b762bc5e8ea7b8391130730c6d8502fc6e69"},{"url":"https://git.kernel.org/stable/c/a0671125d4f55e1e98d9bde8a0b671941987e208"}],"title":"clsact: Fix use-after-free in init/destroy rollback asymmetry","x_generator":{"engine":"bippy-1.2.0"}}}}