{"schema":"threatline.record/2","record":{"id":"CVE-2026-98621","aliases":[],"summary":"net: gue: reject invalid REMCSUM offsets","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: gue: reject invalid REMCSUM offsets\n\nThe REMCSUM option carries an absolute checksum start and checksum field\noffset. gue_remcsum() passes them to skb_remcsum_process(), whose\npartial path stores offset - start in the u16 skb->csum_offset variable.\nIf offset is less than start, this underflows.\n\nA forwarded packet can retain CHECKSUM_PARTIAL and reach a NETIF_F_HW_CSUM\ndriver which trusts the metadata, leading skb_copy_and_csum_dev() to write\ntwo bytes about 64 KiB beyond the destination buffer.\n\nReject reversed tuples in validate_gue_flags(), after the existing length\nvalidation, so all GUE parsers enforce the ordering in one place.","categories":["Operating systems"],"product":"Linux","vendor":"Linux","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98621","source_modified_at":"2026-10-19T09:22:49.371Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"fe881ef11cf0220f118816181930494d484c4883","lessThan":"4b9bc21b2396c396d88dd909caaf73d5be6ff593","status":"affected","versionType":"git"},{"version":"fe881ef11cf0220f118816181930494d484c4883","lessThan":"43efb1f997e976f386aa89716f55870cd2cff9ad","status":"affected","versionType":"git"},{"version":"fe881ef11cf0220f118816181930494d484c4883","lessThan":"1eeec0c51fd5598da44080ed96bbd9880021c28b","status":"affected","versionType":"git"},{"version":"fe881ef11cf0220f118816181930494d484c4883","lessThan":"1d664be4ca49d1696e85239236f4988dfc4653c3","status":"affected","versionType":"git"},{"version":"fe881ef11cf0220f118816181930494d484c4883","lessThan":"97f907203321eee2cc9132d5c9eb47698fb41d35","status":"affected","versionType":"git"},{"version":"fe881ef11cf0220f118816181930494d484c4883","lessThan":"40aeafbcbc7bc4018e8f74bbbb4d29ed8846f57f","status":"affected","versionType":"git"},{"version":"fe881ef11cf0220f118816181930494d484c4883","lessThan":"c20f755338ca234e523dfc943719f194dfc1f903","status":"affected","versionType":"git"},{"version":"fe881ef11cf0220f118816181930494d484c4883","lessThan":"2566866fc30965d915d0b52b5c3323b362619f0e","status":"affected","versionType":"git"}],"defaultStatus":"unaffected"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98621","source_modified_at":"2026-10-19T09:22:49.371Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"4.0","status":"affected"},{"version":"0","lessThan":"4.0","status":"unaffected","versionType":"semver"},{"version":"5.10.271","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.222","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.189","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.158","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-2026-98621","source_modified_at":"2026-10-19T09:22:49.371Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"4b9bc21b2396c396d88dd909caaf73d5be6ff593","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98621","source_modified_at":"2026-10-19T09:22:49.371Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"43efb1f997e976f386aa89716f55870cd2cff9ad","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98621","source_modified_at":"2026-10-19T09:22:49.371Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"1eeec0c51fd5598da44080ed96bbd9880021c28b","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98621","source_modified_at":"2026-10-19T09:22:49.371Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"1d664be4ca49d1696e85239236f4988dfc4653c3","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98621","source_modified_at":"2026-10-19T09:22:49.371Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"97f907203321eee2cc9132d5c9eb47698fb41d35","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98621","source_modified_at":"2026-10-19T09:22:49.371Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"40aeafbcbc7bc4018e8f74bbbb4d29ed8846f57f","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98621","source_modified_at":"2026-10-19T09:22:49.371Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"2566866fc30965d915d0b52b5c3323b362619f0e","basis":"first unaffected version stated in the CVE record"}],"cvss":null,"severity":null,"kev":{"listed":false},"epss":{"probability":0.0021,"percentile":0.10709,"score_date":"2026-10-23"},"published_at":"2026-10-18T15:19:41.211Z","modified_at":"2026-10-19T09:22:49.371Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-98621","fetched_at":"2026-10-23T18:45:31.882637Z","source_modified_at":"2026-10-19T09:22:49.371Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-98621","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/4b9bc21b2396c396d88dd909caaf73d5be6ff593"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/43efb1f997e976f386aa89716f55870cd2cff9ad"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/1eeec0c51fd5598da44080ed96bbd9880021c28b"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/1d664be4ca49d1696e85239236f4988dfc4653c3"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/97f907203321eee2cc9132d5c9eb47698fb41d35"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/40aeafbcbc7bc4018e8f74bbbb4d29ed8846f57f"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/c20f755338ca234e523dfc943719f194dfc1f903"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/2566866fc30965d915d0b52b5c3323b362619f0e"}],"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":"2026-10-19T09:22:49.371Z","content_hash":"5477014a735495d1c61efdf03350ab2a242fc794190ff2690558a20e5c22332f"}}