{"id":"CVE-2026-43452","title":"netfilter: x_tables: guard option walkers against 1-byte tail reads","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: x_tables: guard option walkers against 1-byte tail reads\n\nWhen the last byte of options is a non-single-byte option kind, walkers\nthat advance with i += op[i…","severity":"high","cvss":8.2,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= 2e4e6a17af35be359cc8f1c924f8f198fbd478cc < c2a445367a496a3c25dbc940c10c8bd1cfd4c14a","Linux >= 2e4e6a17af35be359cc8f1c924f8f198fbd478cc < ae1e1267650638136b84c23f2b31250f0ccb6823","Linux >= 2e4e6a17af35be359cc8f1c924f8f198fbd478cc < c39f84e4be1be63fc60ca7141ea7b76edcea5907","Linux >= 2e4e6a17af35be359cc8f1c924f8f198fbd478cc < 9b94f0e42ed248eb31929da84ed9f5310d7ff540","Linux >= 2e4e6a17af35be359cc8f1c924f8f198fbd478cc < 5b18b8b35c7cded2d17b2b2604c9b0694ff48d1c","Linux >= 2e4e6a17af35be359cc8f1c924f8f198fbd478cc < bc18551c6169eac5ed813778d3e3e484002dbbe5","Linux >= 2e4e6a17af35be359cc8f1c924f8f198fbd478cc < d04800323336eebf441d153f43234eac9b833d36","Linux >= 2e4e6a17af35be359cc8f1c924f8f198fbd478cc < cfe770220ac2dbd3e104c6b45094037455da81d4","Linux 2.6.16"],"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"partial","timestamp":"2026-10-16T15:17:27.922262Z"},"published":"2026-05-08","updated":"2026-10-16","sourceUpdated":"2026-10-16T15:20:41.957Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-43452","references":[{"url":"https://git.kernel.org/stable/c/c2a445367a496a3c25dbc940c10c8bd1cfd4c14a"},{"url":"https://git.kernel.org/stable/c/ae1e1267650638136b84c23f2b31250f0ccb6823"},{"url":"https://git.kernel.org/stable/c/c39f84e4be1be63fc60ca7141ea7b76edcea5907"},{"url":"https://git.kernel.org/stable/c/9b94f0e42ed248eb31929da84ed9f5310d7ff540"},{"url":"https://git.kernel.org/stable/c/5b18b8b35c7cded2d17b2b2604c9b0694ff48d1c"},{"url":"https://git.kernel.org/stable/c/bc18551c6169eac5ed813778d3e3e484002dbbe5"},{"url":"https://git.kernel.org/stable/c/d04800323336eebf441d153f43234eac9b833d36"},{"url":"https://git.kernel.org/stable/c/cfe770220ac2dbd3e104c6b45094037455da81d4"}],"tags":["cve.org"],"epss":0.00633,"epssPercentile":0.4928,"ingestedAt":"2026-10-16T17:24:46.696Z","slug":"CVE-2026-43452","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: x_tables: guard option walkers against 1-byte tail reads\n\nWhen the last byte of options is a non-single-byte option kind, walkers\nthat advance with i += op[i + 1] ? : 1 can read op[i + 1] past the end\nof the option area.\n\nAdd an explicit i == optlen - 1 check before dereferencing op[i + 1]\nin xt_tcpudp and xt_dccp option walkers.\n\n## Affected\n\n- `Linux >= 2e4e6a17af35be359cc8f1c924f8f198fbd478cc < c2a445367a496a3c25dbc940c10c8bd1cfd4c14a`\n- `Linux >= 2e4e6a17af35be359cc8f1c924f8f198fbd478cc < ae1e1267650638136b84c23f2b31250f0ccb6823`\n- `Linux >= 2e4e6a17af35be359cc8f1c924f8f198fbd478cc < c39f84e4be1be63fc60ca7141ea7b76edcea5907`\n- `Linux >= 2e4e6a17af35be359cc8f1c924f8f198fbd478cc < 9b94f0e42ed248eb31929da84ed9f5310d7ff540`\n- `Linux >= 2e4e6a17af35be359cc8f1c924f8f198fbd478cc < 5b18b8b35c7cded2d17b2b2604c9b0694ff48d1c`\n- `Linux >= 2e4e6a17af35be359cc8f1c924f8f198fbd478cc < bc18551c6169eac5ed813778d3e3e484002dbbe5`\n- `Linux >= 2e4e6a17af35be359cc8f1c924f8f198fbd478cc < d04800323336eebf441d153f43234eac9b833d36`\n- `Linux >= 2e4e6a17af35be359cc8f1c924f8f198fbd478cc < cfe770220ac2dbd3e104c6b45094037455da81d4`\n- `Linux 2.6.16`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":45,"depthScoreParts":{"impact":45.1,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}