{"id":"CVE-2026-31659","title":"batman-adv: reject oversized global TT response buffers","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nbatman-adv: reject oversized global TT response buffers\n\nbatadv_tt_prepare_tvlv_global_data() builds the allocation length for a\nglobal TT response in 16-bit temporarie…","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b < 7e5d007e0df946bffb8542fb112e0044014a5897","Linux >= 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b < 2997f4bd1f982e7013709946e00be89b507693fa","Linux >= 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b < 95c71365a2222908441b54d6f2c315e0c79fcec3","Linux >= 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b < 69d61639bc7e963c3b645e570279d731e7c89062","Linux >= 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b < f970646b9a39539d1bac86822ac78b5915455ea9","Linux >= 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b < de6c1dc3c7d01a152607e6fcecee4d5288283f10","Linux >= 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b < cf2199171ef799ca7270019125f4a91bd20ad4d9","Linux >= 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b < 3a359bf5c61d52e7f09754108309d637532164a6","Linux 3.13"],"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"total","timestamp":"2026-10-16T15:11:40.590672Z"},"published":"2026-04-24","updated":"2026-10-16","sourceUpdated":"2026-10-16T15:20:20.140Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-31659","references":[{"url":"https://git.kernel.org/stable/c/7e5d007e0df946bffb8542fb112e0044014a5897"},{"url":"https://git.kernel.org/stable/c/2997f4bd1f982e7013709946e00be89b507693fa"},{"url":"https://git.kernel.org/stable/c/95c71365a2222908441b54d6f2c315e0c79fcec3"},{"url":"https://git.kernel.org/stable/c/69d61639bc7e963c3b645e570279d731e7c89062"},{"url":"https://git.kernel.org/stable/c/f970646b9a39539d1bac86822ac78b5915455ea9"},{"url":"https://git.kernel.org/stable/c/de6c1dc3c7d01a152607e6fcecee4d5288283f10"},{"url":"https://git.kernel.org/stable/c/cf2199171ef799ca7270019125f4a91bd20ad4d9"},{"url":"https://git.kernel.org/stable/c/3a359bf5c61d52e7f09754108309d637532164a6"}],"tags":["cve.org"],"epss":0.00421,"epssPercentile":0.34949,"ingestedAt":"2026-10-16T17:24:46.667Z","slug":"CVE-2026-31659","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nbatman-adv: reject oversized global TT response buffers\n\nbatadv_tt_prepare_tvlv_global_data() builds the allocation length for a\nglobal TT response in 16-bit temporaries. When a remote originator\nadvertises a large enough global TT, the TT payload length plus the VLAN\nheader offset can exceed 65535 and wrap before kmalloc().\n\nThe full-table response path still uses the original TT payload length when\nit fills tt_change, so the wrapped allocation is too small and\nbatadv_tt_prepare_tvlv_global_data() writes past the end of the heap object\nbefore the later packet-size check runs.\n\nFix this by rejecting TT responses whose TVLV value length cannot fit in\nthe 16-bit TVLV payload length field.\n\n## Affected\n\n- `Linux >= 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b < 7e5d007e0df946bffb8542fb112e0044014a5897`\n- `Linux >= 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b < 2997f4bd1f982e7013709946e00be89b507693fa`\n- `Linux >= 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b < 95c71365a2222908441b54d6f2c315e0c79fcec3`\n- `Linux >= 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b < 69d61639bc7e963c3b645e570279d731e7c89062`\n- `Linux >= 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b < f970646b9a39539d1bac86822ac78b5915455ea9`\n- `Linux >= 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b < de6c1dc3c7d01a152607e6fcecee4d5288283f10`\n- `Linux >= 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b < cf2199171ef799ca7270019125f4a91bd20ad4d9`\n- `Linux >= 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b < 3a359bf5c61d52e7f09754108309d637532164a6`\n- `Linux 3.13`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"midnight","depthScore":54,"depthScoreParts":{"impact":53.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}