{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2026-23111", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-23111", "idYear": 2026, "status": "PUBLISHED", "publishedAt": "2026-02-13T13:29:55.895Z", "updatedAt": "2026-10-15T01:13:04.873Z", "importedAt": "2026-10-24T01:58:02.025Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "netfilter: nf_tables: fix inverted genmask check in nft_map_catchall_activate()", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_tables: fix inverted genmask check in nft_map_catchall_activate()\n\nnft_map_catchall_activate() has an inverted element activity check\ncompared to its non-catchall counterpart nft_mapelem_activate() and\ncompared to what is logically required.\n\nnft_map_catchall_activate() is called from the abort path to re-activate\ncatchall map elements that were deactivated during a failed transaction.\nIt should skip elements that are already active (they don't need\nre-activation) and process elements that are inactive (they need to be\nrestored). Instead, the current code does the opposite: it skips inactive\nelements and processes active ones.\n\nCompare the non-catchall activate callback, which is correct:\n\n nft_mapelem_activate():\n if (nft_set_elem_active(ext, iter->genmask))\n return 0; /* skip active, process inactive */\n\nWith the buggy catchall version:\n\n nft_map_catchall_activate():\n if (!nft_set_elem_active(ext, genmask))\n continue; /* skip inactive, process active */\n\nThe consequence is that when a DELSET operation is aborted,\nnft_setelem_data_activate() is never called for the catchall element.\nFor NFT_GOTO verdict elements, this means nft_data_hold() is never\ncalled to restore the chain->use reference count. Each abort cycle\npermanently decrements chain->use. Once chain->use reaches zero,\nDELCHAIN succeeds and frees the chain while catchall verdict elements\nstill reference it, resulting in a use-after-free.\n\nThis is exploitable for local privilege escalation from an unprivileged\nuser via user namespaces + nftables on distributions that enable\nCONFIG_USER_NS and CONFIG_NF_TABLES.\n\nFix by removing the negation so the check matches nft_mapelem_activate():\nskip active elements, process inactive ones.", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "25aa2ad37c2162be1c0bc4fe6397f7e4c13f00f8", "status": "affected", "versionType": "git", "lessThan": "8c760ba4e36c750379d13569f23f5a6e185333f5" }, { "version": "d60be2da67d172aecf866302c91ea11533eca4d9", "status": "affected", "versionType": "git", "lessThan": "b9b6573421de51829f7ec1cce76d85f5f6fbbd7f" }, { "version": "628bd3e49cba1c066228e23d71a852c23e26da73", "status": "affected", "versionType": "git", "lessThan": "42c574c1504aa089a0a142e4c13859327570473d" }, { "version": "628bd3e49cba1c066228e23d71a852c23e26da73", "status": "affected", "versionType": "git", "lessThan": "1444ff890b4653add12f734ffeffc173d42862dd" }, { "version": "628bd3e49cba1c066228e23d71a852c23e26da73", "status": "affected", "versionType": "git", "lessThan": "8b68a45f9722f2babe9e7bad00aa74638addf081" }, { "version": "628bd3e49cba1c066228e23d71a852c23e26da73", "status": "affected", "versionType": "git", "lessThan": "f41c5d151078c5348271ffaf8e7410d96f2d82f8" }, { "version": "bc9f791d2593f17e39f87c6e2b3a36549a3705b1", "status": "affected", "versionType": "git" }, { "version": "3c7ec098e3b588434a8b07ea9b5b36f04cef1f50", "status": "affected", "versionType": "git" }, { "version": "a136b7942ad2a50de708f76ea299ccb45ac7a7f9", "status": "affected", "versionType": "git" }, { "version": "dc7cdf8cbcbf8b13de1df93f356ec04cdeef5c41", "status": "affected", "versionType": "git" }, { "version": "5.15.121", "status": "affected", "versionType": "semver", "lessThan": "5.15.200" }, { "version": "6.1.36", "status": "affected", "versionType": "semver", "lessThan": "6.1.163" }, { "version": "4.19.316", "status": "affected", "versionType": "semver", "lessThan": "4.20" }, { "version": "5.4.262", "status": "affected", "versionType": "semver", "lessThan": "5.5" }, { "version": "5.10.188", "status": "affected", "versionType": "semver", "lessThan": "5.11" }, { "version": "6.3.10", "status": "affected", "versionType": "semver", "lessThan": "6.4" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "6.4", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "6.4" }, { "version": "5.15.200", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.163", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.124", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.70", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.18.10", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.18.*" }, { "version": "6.19", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }