{"cve":"CVE-2023-52924","nvd":{"published":"2025-02-05T10:15:21.073","modified":"2026-06-17T06:43:56.690","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_tables: don't skip expired elements during walk\n\nThere is an asymmetry between commit/abort and preparation phase if the\nfollowing conditions are met:\n\n1. set is a verdict map (\"1.2.3.4 : jump foo\")\n2. timeouts are enabled\n\nIn this case, following sequence is problematic:\n\n1. element E in set S refers to chain C\n2. userspace requests removal of set S\n3. kernel does a set walk to decrement chain->use count for all elements\n   from preparation phase\n4. kernel does another set walk to remove elements from the commit phase\n   (or another walk to do a chain->use increment for all elements from\n    abort phase)\n\nIf E has already expired in 1), it will be ignored during list walk, so its use count\nwon't have been changed.\n\nThen, when set is culled, ->destroy callback will zap the element via\nnf_tables_set_elem_destroy(), but this function is only safe for\nelements that have been deactivated earlier from the preparation phase:\nlack of earlier deactivate removes the element but leaks the chain use\ncount, which results in a WARN splat when the chain gets removed later,\nplus a leak of the nft_chain structure.\n\nUpdate pipapo_get() not to skip expired elements, otherwise flush\ncommand reports bogus ENOENT errors.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":[],"references":["https://git.kernel.org/stable/c/1da4874d05da1526b11b82fc7f3c7ac38749ddf8","https://git.kernel.org/stable/c/24138933b97b055d486e8064b4a1721702442a9b","https://git.kernel.org/stable/c/59dab3bf0b8fc08eb802721c0532f13dd89209b8","https://git.kernel.org/stable/c/7c7e658a36f8b1522bd3586d8137e5f93a25ddc5","https://git.kernel.org/stable/c/94313a196b44184b5b52c1876da6a537701b425a"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:59:18.731010617+00:00"},"epss":{"cve":"CVE-2023-52924","score":0.00205,"percentile":0.10542,"date":"2026-11-01"},"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."]}