{"api_version":"1","generated_at":"2026-09-29T03:15:06+00:00","cve":"CVE-2026-90054","urls":{"html":"https://cve.report/CVE-2026-90054","api":"https://cve.report/api/cve/CVE-2026-90054.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-90054","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-90054"},"summary":{"title":"tcp: fix corruption of urgent data on multi-segment retransmit","description":"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.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-17 17:16:53","updated_at":"2026-09-17 17:16:53"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/ebe55406404f3cb28e36d2b668e2c6c05026ec29","name":"https://git.kernel.org/stable/c/ebe55406404f3cb28e36d2b668e2c6c05026ec29","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/711bfd762bec05fb19bc3b17cbb157c39f4e66da","name":"https://git.kernel.org/stable/c/711bfd762bec05fb19bc3b17cbb157c39f4e66da","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/47eb90299e6882d6445672530dd7c51ac33ebdbd","name":"https://git.kernel.org/stable/c/47eb90299e6882d6445672530dd7c51ac33ebdbd","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/8eb51013b6308870479a64b4a2a018697b997849","name":"https://git.kernel.org/stable/c/8eb51013b6308870479a64b4a2a018697b997849","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/3d4e005c198dc410ad568f832bffa7569c059ff8","name":"https://git.kernel.org/stable/c/3d4e005c198dc410ad568f832bffa7569c059ff8","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/4fd2ee4ac154c204d95d8db72221446dac5af9b8","name":"https://git.kernel.org/stable/c/4fd2ee4ac154c204d95d8db72221446dac5af9b8","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/b8f08a94b2a4addc39249dcf9c792e786108621b","name":"https://git.kernel.org/stable/c/b8f08a94b2a4addc39249dcf9c792e786108621b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/ce2b807f42ed5e55567b8864ab72963f90779270","name":"https://git.kernel.org/stable/c/ce2b807f42ed5e55567b8864ab72963f90779270","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-90054","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-90054","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 10d3be569243def8d92ac3722395ef5a59c504e6 8eb51013b6308870479a64b4a2a018697b997849 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 10d3be569243def8d92ac3722395ef5a59c504e6 711bfd762bec05fb19bc3b17cbb157c39f4e66da git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 10d3be569243def8d92ac3722395ef5a59c504e6 3d4e005c198dc410ad568f832bffa7569c059ff8 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 10d3be569243def8d92ac3722395ef5a59c504e6 4fd2ee4ac154c204d95d8db72221446dac5af9b8 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 10d3be569243def8d92ac3722395ef5a59c504e6 ebe55406404f3cb28e36d2b668e2c6c05026ec29 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 10d3be569243def8d92ac3722395ef5a59c504e6 b8f08a94b2a4addc39249dcf9c792e786108621b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 10d3be569243def8d92ac3722395ef5a59c504e6 47eb90299e6882d6445672530dd7c51ac33ebdbd git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 10d3be569243def8d92ac3722395ef5a59c504e6 ce2b807f42ed5e55567b8864ab72963f90779270 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4.7","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 4.7 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.10.270 5.10.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.15.221 5.15.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.188 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.157 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.110 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.52 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.6 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3-rc1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/ipv4/tcp_output.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"8eb51013b6308870479a64b4a2a018697b997849","status":"affected","version":"10d3be569243def8d92ac3722395ef5a59c504e6","versionType":"git"},{"lessThan":"711bfd762bec05fb19bc3b17cbb157c39f4e66da","status":"affected","version":"10d3be569243def8d92ac3722395ef5a59c504e6","versionType":"git"},{"lessThan":"3d4e005c198dc410ad568f832bffa7569c059ff8","status":"affected","version":"10d3be569243def8d92ac3722395ef5a59c504e6","versionType":"git"},{"lessThan":"4fd2ee4ac154c204d95d8db72221446dac5af9b8","status":"affected","version":"10d3be569243def8d92ac3722395ef5a59c504e6","versionType":"git"},{"lessThan":"ebe55406404f3cb28e36d2b668e2c6c05026ec29","status":"affected","version":"10d3be569243def8d92ac3722395ef5a59c504e6","versionType":"git"},{"lessThan":"b8f08a94b2a4addc39249dcf9c792e786108621b","status":"affected","version":"10d3be569243def8d92ac3722395ef5a59c504e6","versionType":"git"},{"lessThan":"47eb90299e6882d6445672530dd7c51ac33ebdbd","status":"affected","version":"10d3be569243def8d92ac3722395ef5a59c504e6","versionType":"git"},{"lessThan":"ce2b807f42ed5e55567b8864ab72963f90779270","status":"affected","version":"10d3be569243def8d92ac3722395ef5a59c504e6","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/ipv4/tcp_output.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"4.7"},{"lessThan":"4.7","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"5.10.*","status":"unaffected","version":"5.10.270","versionType":"semver"},{"lessThanOrEqual":"5.15.*","status":"unaffected","version":"5.15.221","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.188","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.157","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.110","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.52","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.6","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3-rc1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.10.270","versionStartIncluding":"4.7","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.15.221","versionStartIncluding":"4.7","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.188","versionStartIncluding":"4.7","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.157","versionStartIncluding":"4.7","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.110","versionStartIncluding":"4.7","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.52","versionStartIncluding":"4.7","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.6","versionStartIncluding":"4.7","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc1","versionStartIncluding":"4.7","vulnerable":true}],"negate":false,"operator":"OR"}]}],"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."}],"providerMetadata":{"dateUpdated":"2026-09-17T16:05:39.632Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"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"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-90054","datePublished":"2026-09-17T16:05:39.632Z","dateReserved":"2026-09-11T19:38:34.783Z","dateUpdated":"2026-09-17T16:05:39.632Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-17 17:16:53","lastModifiedDate":"2026-09-17 17:16:53","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"90054","Ordinal":"1","Title":"tcp: fix corruption of urgent data on multi-segment retransmit","CVE":"CVE-2026-90054","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"90054","Ordinal":"1","NoteData":"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.","Type":"Description","Title":"tcp: fix corruption of urgent data on multi-segment retransmit"}]}}}