{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-90054", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.783Z", "datePublished": "2026-09-17T16:05:39.632Z", "dateUpdated": "2026-10-19T08:57:11.615Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:57:11.615Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntcp: fix corruption of urgent data on multi-segment retransmit\n\nOn the normal xmit path, while in urgent mode we refuse to build a\nmulti-segment TSO packet, so every segment gets its own urg_ptr:\n\n\t/* tcp_write_xmit() */\n\tlimit = mss_now;\n\tif (tso_segs > 1 && !tcp_urg_mode(tp))\n\t\tlimit = tcp_mss_split_point(...);\n\nThe retransmit path has no such guard. __tcp_retransmit_skb() builds a\nsegs > 1 skb and hands it to the GSO layer, which only advances th->seq\nper segment and copies urg_ptr verbatim:\n\n\t/* __tcp_retransmit_skb() */\n\tlen = cur_mss * segs;\t\t/* segs > 1, no urg_mode check */\n\t...\n\t/* tcp_gso_segment(): bumps seq only, urg_ptr is copied */\n\nurg_ptr is an offset from the segment's own seq, so a copied value points\nat a different place on each segment. The receiver rebuilds the absolute\nurgent seq as seg.seq + urg_ptr, so it walks a moving urgent point instead\nof the one OOB byte:\n\n\tseg1 seq 1 urg_ptr 5001 -> urgent @ 5001 (ok)\n\tseg2 seq 1001 urg_ptr 5001 -> urgent @ 6001 (wrong, +MSS)\n\tseg3 seq 2001 urg_ptr 5001 -> urgent @ 7001 (wrong, +2*MSS)\n\nThe real OOB byte is never pointed at, so the receiver stops splicing it\nout and delivers it as normal in-band data, corrupting the stream.\n\nGuard the retransmit length like the xmit path: keep segs = 1 while in\nurgent mode." } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/ipv4/tcp_output.c" ], "versions": [ { "version": "10d3be569243def8d92ac3722395ef5a59c504e6", "lessThan": "8eb51013b6308870479a64b4a2a018697b997849", "status": "affected", "versionType": "git" }, { "version": "10d3be569243def8d92ac3722395ef5a59c504e6", "lessThan": "711bfd762bec05fb19bc3b17cbb157c39f4e66da", "status": "affected", "versionType": "git" }, { "version": "10d3be569243def8d92ac3722395ef5a59c504e6", "lessThan": "3d4e005c198dc410ad568f832bffa7569c059ff8", "status": "affected", "versionType": "git" }, { "version": "10d3be569243def8d92ac3722395ef5a59c504e6", "lessThan": "4fd2ee4ac154c204d95d8db72221446dac5af9b8", "status": "affected", "versionType": "git" }, { "version": "10d3be569243def8d92ac3722395ef5a59c504e6", "lessThan": "ebe55406404f3cb28e36d2b668e2c6c05026ec29", "status": "affected", "versionType": "git" }, { "version": "10d3be569243def8d92ac3722395ef5a59c504e6", "lessThan": "b8f08a94b2a4addc39249dcf9c792e786108621b", "status": "affected", "versionType": "git" }, { "version": "10d3be569243def8d92ac3722395ef5a59c504e6", "lessThan": "47eb90299e6882d6445672530dd7c51ac33ebdbd", "status": "affected", "versionType": "git" }, { "version": "10d3be569243def8d92ac3722395ef5a59c504e6", "lessThan": "ce2b807f42ed5e55567b8864ab72963f90779270", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/ipv4/tcp_output.c" ], "versions": [ { "version": "4.7", "status": "affected" }, { "version": "0", "lessThan": "4.7", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.270", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.221", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.188", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.157", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.110", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.52", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.6", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "5.10.270" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "5.15.221" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "6.1.188" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "6.6.157" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "6.12.110" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "6.18.52" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "7.2.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/8eb51013b6308870479a64b4a2a018697b997849" }, { "url": "https://git.kernel.org/stable/c/711bfd762bec05fb19bc3b17cbb157c39f4e66da" }, { "url": "https://git.kernel.org/stable/c/3d4e005c198dc410ad568f832bffa7569c059ff8" }, { "url": "https://git.kernel.org/stable/c/4fd2ee4ac154c204d95d8db72221446dac5af9b8" }, { "url": "https://git.kernel.org/stable/c/ebe55406404f3cb28e36d2b668e2c6c05026ec29" }, { "url": "https://git.kernel.org/stable/c/b8f08a94b2a4addc39249dcf9c792e786108621b" }, { "url": "https://git.kernel.org/stable/c/47eb90299e6882d6445672530dd7c51ac33ebdbd" }, { "url": "https://git.kernel.org/stable/c/ce2b807f42ed5e55567b8864ab72963f90779270" } ], "title": "tcp: fix corruption of urgent data on multi-segment retransmit", "x_generator": { "engine": "bippy-1.2.0" } } } }