{"id":"CVE-2023-52924","title":"netfilter: nf_tables: don't skip expired elements during walk","summary":"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.…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 9d0982927e79049675cb6c6c04a0ebb3dad5a434 < 94313a196b44184b5b52c1876da6a537701b425a","Linux >= 9d0982927e79049675cb6c6c04a0ebb3dad5a434 < 1da4874d05da1526b11b82fc7f3c7ac38749ddf8","Linux >= 9d0982927e79049675cb6c6c04a0ebb3dad5a434 < b15ea4017af82011dd55225ce77cce3d4dfc169c","Linux >= 9d0982927e79049675cb6c6c04a0ebb3dad5a434 < 7c7e658a36f8b1522bd3586d8137e5f93a25ddc5","Linux >= 9d0982927e79049675cb6c6c04a0ebb3dad5a434 < 59dab3bf0b8fc08eb802721c0532f13dd89209b8","Linux >= 9d0982927e79049675cb6c6c04a0ebb3dad5a434 < bd156ce9553dcaf2d6ee2c825d1a5a1718e86524","Linux >= 9d0982927e79049675cb6c6c04a0ebb3dad5a434 < 24138933b97b055d486e8064b4a1721702442a9b","Linux 4.1"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-05T20:13:51.204735Z"},"published":"2025-02-05","updated":"2026-11-05","sourceUpdated":"2026-11-05T20:20:52.702Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2023-52924","references":[{"url":"https://git.kernel.org/stable/c/94313a196b44184b5b52c1876da6a537701b425a"},{"url":"https://git.kernel.org/stable/c/1da4874d05da1526b11b82fc7f3c7ac38749ddf8"},{"url":"https://git.kernel.org/stable/c/b15ea4017af82011dd55225ce77cce3d4dfc169c"},{"url":"https://git.kernel.org/stable/c/7c7e658a36f8b1522bd3586d8137e5f93a25ddc5"},{"url":"https://git.kernel.org/stable/c/59dab3bf0b8fc08eb802721c0532f13dd89209b8"},{"url":"https://git.kernel.org/stable/c/bd156ce9553dcaf2d6ee2c825d1a5a1718e86524"},{"url":"https://git.kernel.org/stable/c/24138933b97b055d486e8064b4a1721702442a9b"}],"tags":["cve.org"],"epss":0.00215,"epssPercentile":0.1192,"ingestedAt":"2026-11-05T22:38:31.750Z","slug":"CVE-2023-52924","body":"## Overview\n\nIn 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.\n\n## Affected\n\n- `Linux >= 9d0982927e79049675cb6c6c04a0ebb3dad5a434 < 94313a196b44184b5b52c1876da6a537701b425a`\n- `Linux >= 9d0982927e79049675cb6c6c04a0ebb3dad5a434 < 1da4874d05da1526b11b82fc7f3c7ac38749ddf8`\n- `Linux >= 9d0982927e79049675cb6c6c04a0ebb3dad5a434 < b15ea4017af82011dd55225ce77cce3d4dfc169c`\n- `Linux >= 9d0982927e79049675cb6c6c04a0ebb3dad5a434 < 7c7e658a36f8b1522bd3586d8137e5f93a25ddc5`\n- `Linux >= 9d0982927e79049675cb6c6c04a0ebb3dad5a434 < 59dab3bf0b8fc08eb802721c0532f13dd89209b8`\n- `Linux >= 9d0982927e79049675cb6c6c04a0ebb3dad5a434 < bd156ce9553dcaf2d6ee2c825d1a5a1718e86524`\n- `Linux >= 9d0982927e79049675cb6c6c04a0ebb3dad5a434 < 24138933b97b055d486e8064b4a1721702442a9b`\n- `Linux 4.1`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}