{"id":"CVE-2026-52915","title":"netfilter: ip6t_hbh: reject oversized option lists","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: ip6t_hbh: reject oversized option lists\n\nstruct ip6t_opts stores at most IP6T_OPTS_OPTSNR option descriptors,\nbut hbh_mt6_check() does not reject larger opts…","severity":"high","cvss":7.1,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 2d523ba48d4ecc46acfb6aba548292cfcce1ac02","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 588933f1a2ca5ff99274f8c9f25dc3a25d0191c3","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 784aadea7a108c9f90985683caa87fb0198c6a39","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 41ec2e242f1702e8370ddfe14d22b7a766021c3e","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < db0250470f023f159094052c0bd5ab026a88ae93","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 57b0ac5e1b46f1f0338dff392ef2092e2871b412","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 6feb43c0995ab3a9c826707eb46541a1696fe4f7","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 4322dcde6b4173c2d8e8e6118ed290794263bcc8","Linux 2.6.12"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-10-16T15:22:35.445064Z"},"published":"2026-06-24","updated":"2026-10-16","sourceUpdated":"2026-10-16T15:31:18.621Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-52915","references":[{"url":"https://git.kernel.org/stable/c/2d523ba48d4ecc46acfb6aba548292cfcce1ac02"},{"url":"https://git.kernel.org/stable/c/588933f1a2ca5ff99274f8c9f25dc3a25d0191c3"},{"url":"https://git.kernel.org/stable/c/784aadea7a108c9f90985683caa87fb0198c6a39"},{"url":"https://git.kernel.org/stable/c/41ec2e242f1702e8370ddfe14d22b7a766021c3e"},{"url":"https://git.kernel.org/stable/c/db0250470f023f159094052c0bd5ab026a88ae93"},{"url":"https://git.kernel.org/stable/c/57b0ac5e1b46f1f0338dff392ef2092e2871b412"},{"url":"https://git.kernel.org/stable/c/6feb43c0995ab3a9c826707eb46541a1696fe4f7"},{"url":"https://git.kernel.org/stable/c/4322dcde6b4173c2d8e8e6118ed290794263bcc8"}],"tags":["cve.org"],"epss":0.00126,"epssPercentile":0.02041,"ingestedAt":"2026-10-16T17:24:46.719Z","slug":"CVE-2026-52915","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: ip6t_hbh: reject oversized option lists\n\nstruct ip6t_opts stores at most IP6T_OPTS_OPTSNR option descriptors,\nbut hbh_mt6_check() does not reject larger optsnr values supplied from\nuserspace.\n\nValidate optsnr in the rule setup path so only match data that fits the\nfixed-size opts array can be installed. This follows the existing xtables\npattern of rejecting invalid user-provided counts in checkentry() and\nkeeps the packet matching path unchanged.\n\n`struct ip6t_opts` has a fixed `opts[IP6T_OPTS_OPTSNR]` array,\nwhere `IP6T_OPTS_OPTSNR` is 16, then off-by-one array access is possible:\n\n[  137.924693][ T8692] UBSAN: array-index-out-of-bounds in ../net/ipv6/netfilter/ip6t_hbh.c:110:29\n[  137.926167][ T8692] index 16 is out of range for type '__u16 [16]'\n\n## Affected\n\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 2d523ba48d4ecc46acfb6aba548292cfcce1ac02`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 588933f1a2ca5ff99274f8c9f25dc3a25d0191c3`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 784aadea7a108c9f90985683caa87fb0198c6a39`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 41ec2e242f1702e8370ddfe14d22b7a766021c3e`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < db0250470f023f159094052c0bd5ab026a88ae93`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 57b0ac5e1b46f1f0338dff392ef2092e2871b412`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 6feb43c0995ab3a9c826707eb46541a1696fe4f7`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 4322dcde6b4173c2d8e8e6118ed290794263bcc8`\n- `Linux 2.6.12`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":39.1,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}