{"id":"CVE-2026-98631","state":"PUBLISHED","title":"xsk: Use a 32-bit compare in xsk_map_gen_lookup","description":"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-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.","publishedAt":"2026-10-18T15:19:53.529Z","updatedAt":"2026-10-19T09:22:59.147Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"e65650f291ee72fc578d6346080fc4699204ef2c","status":"affected","lessThan":"c6d5c582d55a8f229d75e98d62eaa065b0deb18d","versionType":"git"},{"version":"e65650f291ee72fc578d6346080fc4699204ef2c","status":"affected","lessThan":"227ec890559e922e235eb543646e3bf0bd8269b0","versionType":"git"},{"version":"e65650f291ee72fc578d6346080fc4699204ef2c","status":"affected","lessThan":"11d9be35c1f4233798e99be98bc474f83a254c6c","versionType":"git"},{"version":"e65650f291ee72fc578d6346080fc4699204ef2c","status":"affected","lessThan":"123f90f394ca404ab8796a7c8072ff7fa5b65a9c","versionType":"git"},{"version":"e65650f291ee72fc578d6346080fc4699204ef2c","status":"affected","lessThan":"36461e58f88a1b723f86693f437ac12e60ff4363","versionType":"git"},{"version":"e65650f291ee72fc578d6346080fc4699204ef2c","status":"affected","lessThan":"b5c0cff0c5331582ab01c4c423731453a8381acc","versionType":"git"},{"version":"e65650f291ee72fc578d6346080fc4699204ef2c","status":"affected","lessThan":"3c1e0a4bc156b8d5c5772dbc76b9ea74dce5ca24","versionType":"git"},{"version":"e65650f291ee72fc578d6346080fc4699204ef2c","status":"affected","lessThan":"70504de0bb627848667207bec7ccfd647deb8814","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/xdp/xskmap.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.5","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.5","versionType":"semver"},{"version":"5.10.271","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.222","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.189","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.158","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.112","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.55","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.9","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/xdp/xskmap.c"]}],"references":["https://git.kernel.org/stable/c/c6d5c582d55a8f229d75e98d62eaa065b0deb18d","https://git.kernel.org/stable/c/227ec890559e922e235eb543646e3bf0bd8269b0","https://git.kernel.org/stable/c/11d9be35c1f4233798e99be98bc474f83a254c6c","https://git.kernel.org/stable/c/123f90f394ca404ab8796a7c8072ff7fa5b65a9c","https://git.kernel.org/stable/c/36461e58f88a1b723f86693f437ac12e60ff4363","https://git.kernel.org/stable/c/b5c0cff0c5331582ab01c4c423731453a8381acc","https://git.kernel.org/stable/c/3c1e0a4bc156b8d5c5772dbc76b9ea74dce5ca24","https://git.kernel.org/stable/c/70504de0bb627848667207bec7ccfd647deb8814"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:43.249Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/98xxx/CVE-2026-98631.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-98631","state":"PUBLISHED","datePublished":"2026-10-18T15:19:53.529Z","dateUpdated":"2026-10-19T09:22:59.147Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-25T10:25:14.361Z"},"containers":{"cna":{"title":"xsk: Use a 32-bit compare in xsk_map_gen_lookup","descriptions":[{"lang":"en","value":"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-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."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"e65650f291ee72fc578d6346080fc4699204ef2c","status":"affected","lessThan":"c6d5c582d55a8f229d75e98d62eaa065b0deb18d","versionType":"git"},{"version":"e65650f291ee72fc578d6346080fc4699204ef2c","status":"affected","lessThan":"227ec890559e922e235eb543646e3bf0bd8269b0","versionType":"git"},{"version":"e65650f291ee72fc578d6346080fc4699204ef2c","status":"affected","lessThan":"11d9be35c1f4233798e99be98bc474f83a254c6c","versionType":"git"},{"version":"e65650f291ee72fc578d6346080fc4699204ef2c","status":"affected","lessThan":"123f90f394ca404ab8796a7c8072ff7fa5b65a9c","versionType":"git"},{"version":"e65650f291ee72fc578d6346080fc4699204ef2c","status":"affected","lessThan":"36461e58f88a1b723f86693f437ac12e60ff4363","versionType":"git"},{"version":"e65650f291ee72fc578d6346080fc4699204ef2c","status":"affected","lessThan":"b5c0cff0c5331582ab01c4c423731453a8381acc","versionType":"git"},{"version":"e65650f291ee72fc578d6346080fc4699204ef2c","status":"affected","lessThan":"3c1e0a4bc156b8d5c5772dbc76b9ea74dce5ca24","versionType":"git"},{"version":"e65650f291ee72fc578d6346080fc4699204ef2c","status":"affected","lessThan":"70504de0bb627848667207bec7ccfd647deb8814","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/xdp/xskmap.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.5","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.5","versionType":"semver"},{"version":"5.10.271","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.222","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.189","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.158","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.112","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.55","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.9","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/xdp/xskmap.c"]}],"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"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T09:22:59.147Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"5.10.271"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"5.15.222"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"6.1.189"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"6.6.158"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"6.12.112"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"6.18.55"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"7.2.9"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}