{"schema":"threatline.record/2","record":{"id":"CVE-2026-98493","aliases":[],"summary":"net: ipconfig: bound DHCP option construction","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: ipconfig: bound DHCP option construction\n\nic_dhcp_init_options() appends the hostname (option 12), vendor-class\n(option 60) and client-ID (option 61) options into the fixed 312-byte\nbootp_pkt.exten[] buffer.  Only the client-ID branch checked the\nremaining space; the hostname and vendor-class writes were unbounded.\n\nA 64-byte hostname together with the maximum 252-byte dhcpclass=\nidentifier needs 18 + (2 + 64) + (2 + 252) = 338 of the 312 available\nbytes even before the terminating END marker, so the vendor-class memcpy\nruns past the end of exten[].  With CONFIG_FORTIFY_SOURCE this is\nreported as a field-spanning write and, when the kernel is booted with\npanic_on_warn=1, aborts boot with a panic.\n\nRoute the optional options through a common helper that makes sure the\noption, its 2-byte header and the END marker all fit and drops an option\nthat would not.  Configurations with short options keep sending exactly\nthe same bytes as before.","categories":["Operating systems"],"product":"Linux","vendor":"Linux","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98493","source_modified_at":"2026-10-21T12:55:14.581Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"130c0f47fdf9c533deb1136cad5136f6cb7020f0","lessThan":"38a6a118260ebfc82d0c653194d616bdfbd236ac","status":"affected","versionType":"git"},{"version":"130c0f47fdf9c533deb1136cad5136f6cb7020f0","lessThan":"abcba6f080c63e403037ecdffde43170d242376a","status":"affected","versionType":"git"},{"version":"130c0f47fdf9c533deb1136cad5136f6cb7020f0","lessThan":"24e79508b237dd2a69bc6fb6ac5cf7f126178307","status":"affected","versionType":"git"},{"version":"130c0f47fdf9c533deb1136cad5136f6cb7020f0","lessThan":"cbaad2922bd5d4d303055ae9afecc8999e6b40c9","status":"affected","versionType":"git"},{"version":"130c0f47fdf9c533deb1136cad5136f6cb7020f0","lessThan":"e47a1958e12abc3a17b5231a4f21c8f1bf662e08","status":"affected","versionType":"git"}],"defaultStatus":"unaffected"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98493","source_modified_at":"2026-10-21T12:55:14.581Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"2.6.36","status":"affected"},{"version":"0","lessThan":"2.6.36","status":"unaffected","versionType":"semver"},{"version":"6.6.160","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.112","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.55","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.9","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}],"defaultStatus":"affected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98493","source_modified_at":"2026-10-21T12:55:14.581Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"38a6a118260ebfc82d0c653194d616bdfbd236ac","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98493","source_modified_at":"2026-10-21T12:55:14.581Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"24e79508b237dd2a69bc6fb6ac5cf7f126178307","basis":"first unaffected version stated in the CVE record"}],"cvss":null,"severity":null,"kev":{"listed":false},"epss":{"probability":0.002,"percentile":0.09335,"score_date":"2026-10-23"},"published_at":"2026-10-18T15:16:22.301Z","modified_at":"2026-10-21T12:55:14.581Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-98493","fetched_at":"2026-10-23T18:45:31.882637Z","source_modified_at":"2026-10-21T12:55:14.581Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-98493","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://git.kernel.org/stable/c/38a6a118260ebfc82d0c653194d616bdfbd236ac"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/abcba6f080c63e403037ecdffde43170d242376a"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/24e79508b237dd2a69bc6fb6ac5cf7f126178307"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/cbaad2922bd5d4d303055ae9afecc8999e6b40c9"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/e47a1958e12abc3a17b5231a4f21c8f1bf662e08"}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-10-21T12:55:14.581Z","content_hash":"63f3504df04ae0bce4b0ef576c303a2f107eceee03f224cc4bb340151fadef68"}}