{"id":"CVE-2026-98631","title":"xsk: Use a 32-bit compare in xsk_map_gen_lookup","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nxsk: Use a 32-bit compare in xsk_map_gen_lookup\n\nxsk_map_gen_lookup() loads a u32 key and compares it with max_entries\nusing BPF_JMP_IMM. BPF immediates are sign-extend…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= e65650f291ee72fc578d6346080fc4699204ef2c < c6d5c582d55a8f229d75e98d62eaa065b0deb18d","Linux >= e65650f291ee72fc578d6346080fc4699204ef2c < 227ec890559e922e235eb543646e3bf0bd8269b0","Linux >= e65650f291ee72fc578d6346080fc4699204ef2c < 11d9be35c1f4233798e99be98bc474f83a254c6c","Linux >= e65650f291ee72fc578d6346080fc4699204ef2c < 123f90f394ca404ab8796a7c8072ff7fa5b65a9c","Linux >= e65650f291ee72fc578d6346080fc4699204ef2c < 36461e58f88a1b723f86693f437ac12e60ff4363","Linux >= e65650f291ee72fc578d6346080fc4699204ef2c < b5c0cff0c5331582ab01c4c423731453a8381acc","Linux >= e65650f291ee72fc578d6346080fc4699204ef2c < 3c1e0a4bc156b8d5c5772dbc76b9ea74dce5ca24","Linux >= e65650f291ee72fc578d6346080fc4699204ef2c < 70504de0bb627848667207bec7ccfd647deb8814","Linux 5.5"],"published":"2026-10-18","updated":"2026-10-18","sourceUpdated":"2026-10-18T15:19:53.529Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98631","references":[{"url":"https://git.kernel.org/stable/c/c6d5c582d55a8f229d75e98d62eaa065b0deb18d"},{"url":"https://git.kernel.org/stable/c/227ec890559e922e235eb543646e3bf0bd8269b0"},{"url":"https://git.kernel.org/stable/c/11d9be35c1f4233798e99be98bc474f83a254c6c"},{"url":"https://git.kernel.org/stable/c/123f90f394ca404ab8796a7c8072ff7fa5b65a9c"},{"url":"https://git.kernel.org/stable/c/36461e58f88a1b723f86693f437ac12e60ff4363"},{"url":"https://git.kernel.org/stable/c/b5c0cff0c5331582ab01c4c423731453a8381acc"},{"url":"https://git.kernel.org/stable/c/3c1e0a4bc156b8d5c5772dbc76b9ea74dce5ca24"},{"url":"https://git.kernel.org/stable/c/70504de0bb627848667207bec7ccfd647deb8814"}],"tags":["cve.org"],"ingestedAt":"2026-10-18T15:45:12.234Z","slug":"CVE-2026-98631","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nxsk: Use a 32-bit compare in xsk_map_gen_lookup\n\nxsk_map_gen_lookup() loads a u32 key and compares it with max_entries\nusing BPF_JMP_IMM. BPF immediates are sign-extended to 64 bits, so a\nmax_entries value of 0x80000000 or higher becomes a threshold larger\nthan every zero-extended 32-bit key. An out-of-range index then skips\nthe bounds check and the generated lookup reads past xsk_map[].\n\nCompare with BPF_JMP32_IMM so the check stays in 32-bit unsigned range.\n\n## Affected\n\n- `Linux >= e65650f291ee72fc578d6346080fc4699204ef2c < c6d5c582d55a8f229d75e98d62eaa065b0deb18d`\n- `Linux >= e65650f291ee72fc578d6346080fc4699204ef2c < 227ec890559e922e235eb543646e3bf0bd8269b0`\n- `Linux >= e65650f291ee72fc578d6346080fc4699204ef2c < 11d9be35c1f4233798e99be98bc474f83a254c6c`\n- `Linux >= e65650f291ee72fc578d6346080fc4699204ef2c < 123f90f394ca404ab8796a7c8072ff7fa5b65a9c`\n- `Linux >= e65650f291ee72fc578d6346080fc4699204ef2c < 36461e58f88a1b723f86693f437ac12e60ff4363`\n- `Linux >= e65650f291ee72fc578d6346080fc4699204ef2c < b5c0cff0c5331582ab01c4c423731453a8381acc`\n- `Linux >= e65650f291ee72fc578d6346080fc4699204ef2c < 3c1e0a4bc156b8d5c5772dbc76b9ea74dce5ca24`\n- `Linux >= e65650f291ee72fc578d6346080fc4699204ef2c < 70504de0bb627848667207bec7ccfd647deb8814`\n- `Linux 5.5`\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":[]}