{"id":"CVE-2026-89478","title":"sctp: drop a chunk if its transport was removed","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: drop a chunk if its transport was removed\n\nsctp_rcv() resolves the transport once per packet and leaves it in\nchunk->transport. The lookup reference, or the one s…","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cvssSource":"cna","cwe":["CWE-825"],"vendor":"Linux","product":"Linux","affected":["Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 3fc072e7cb4a0ff251d13cfc2d24f62489cd9386","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < d7cb5ad832095dc4becfdb2a36007ffd50e49fb0","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 0422b092a3d43ca462932ff9f747731ca078d1d4","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 928fd7920ba37cc5637a211b9be979083413a2fa","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < c6c86a5e62a4fec36692ddd64b9144b660f71f96","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 1035bdef1efb9b1076d1a57b81e08c637ff08ecc","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 3537961df2163258bddc230db0e18dc14e925ea6","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 03a9d10ecf71f54b2af8020935f2033d4a132be5","Linux 2.6.12"],"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"total","timestamp":"2026-10-16T19:22:25.085426Z"},"published":"2026-09-11","updated":"2026-10-19","sourceUpdated":"2026-10-19T08:47:27.202Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-89478","references":[{"url":"https://git.kernel.org/stable/c/3fc072e7cb4a0ff251d13cfc2d24f62489cd9386"},{"url":"https://git.kernel.org/stable/c/d7cb5ad832095dc4becfdb2a36007ffd50e49fb0"},{"url":"https://git.kernel.org/stable/c/0422b092a3d43ca462932ff9f747731ca078d1d4"},{"url":"https://git.kernel.org/stable/c/928fd7920ba37cc5637a211b9be979083413a2fa"},{"url":"https://git.kernel.org/stable/c/c6c86a5e62a4fec36692ddd64b9144b660f71f96"},{"url":"https://git.kernel.org/stable/c/1035bdef1efb9b1076d1a57b81e08c637ff08ecc"},{"url":"https://git.kernel.org/stable/c/3537961df2163258bddc230db0e18dc14e925ea6"},{"url":"https://git.kernel.org/stable/c/03a9d10ecf71f54b2af8020935f2033d4a132be5"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89478.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-89478"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2532439"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89478"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89478"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89478.mbox"}],"tags":["cve.org","csaf","vex","red-hat","score-dispute"],"epss":0.00514,"epssPercentile":0.43609,"scores":{"cna":9.8,"vendor":7},"ingestedAt":"2026-09-14T15:23:07.453Z","slug":"CVE-2026-89478","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nsctp: drop a chunk if its transport was removed\n\nsctp_rcv() resolves the transport once per packet and leaves it in\nchunk->transport. The lookup reference, or the one sctp_add_backlog() takes\nif the socket is owned by userspace, keeps it around until the chunk has\nbeen processed.\n\nAn authenticated ASCONF DEL-IP can remove it in the meantime.\nsctp_assoc_rm_peer() takes the transport out of the association and calls\nsctp_transport_free(), which tags it dead and drops the reference the\nassociation held. There is a window on both paths: the packet can sit on\nthe socket backlog, and on the direct path the lookup completes before\nbh_lock_sock().\n\nThe DATA chunk in that packet puts the removed transport back into\nasoc->peer.last_data_from. Once the packet is done that reference goes\naway and the transport is freed by RCU, so the next delayed SACK carries\nthe pointer into the SACK chunk and sctp_outq_select_transport() reads the\nfreed transport's state.\n\nDrop the chunk in sctp_inq_push(), next to the existing rcvr->dead check.\nBoth paths reach it with the association's socket lock held. The peer\nretransmits it.\n\n## Affected\n\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 3fc072e7cb4a0ff251d13cfc2d24f62489cd9386`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < d7cb5ad832095dc4becfdb2a36007ffd50e49fb0`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 0422b092a3d43ca462932ff9f747731ca078d1d4`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 928fd7920ba37cc5637a211b9be979083413a2fa`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < c6c86a5e62a4fec36692ddd64b9144b660f71f96`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 1035bdef1efb9b1076d1a57b81e08c637ff08ecc`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 3537961df2163258bddc230db0e18dc14e925ea6`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 03a9d10ecf71f54b2af8020935f2033d4a132be5`\n- `Linux 2.6.12`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, … · updated 2026-09-15 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89478.json)","depth":"midnight","depthScore":54,"depthScoreParts":{"impact":53.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":223315,"id":"CVE-2026-89478","ts":1792180054235,"field":"cvss","old":"7","new":"9.8"},{"seq":223314,"id":"CVE-2026-89478","ts":1792180054235,"field":"severity","old":"high","new":"critical"},{"seq":203893,"id":"CVE-2026-89478","ts":1789490212683,"field":"cvss","old":"9.8","new":"7"},{"seq":203892,"id":"CVE-2026-89478","ts":1789490212683,"field":"severity","old":"critical","new":"high"},{"seq":198030,"id":"CVE-2026-89478","ts":1789384321464,"field":"cvss","old":"5.9","new":"9.8"},{"seq":198029,"id":"CVE-2026-89478","ts":1789384321464,"field":"severity","old":"medium","new":"critical"},{"seq":183794,"id":"CVE-2026-89478","ts":1789356677417,"field":"cvss","old":"9.8","new":"5.9"},{"seq":183793,"id":"CVE-2026-89478","ts":1789356677417,"field":"severity","old":"critical","new":"medium"},{"seq":153256,"id":"CVE-2026-89478","ts":1789285349764,"field":"cvss","old":null,"new":"9.8"},{"seq":153255,"id":"CVE-2026-89478","ts":1789285349764,"field":"severity","old":"none","new":"critical"},{"seq":147247,"id":"CVE-2026-89478","ts":1789270204202,"field":"cvss","old":null,"new":"5.9"},{"seq":147246,"id":"CVE-2026-89478","ts":1789270204202,"field":"severity","old":"none","new":"medium"},{"seq":109010,"id":"CVE-2026-89478","ts":1789183729939,"field":"cvss","old":null,"new":"5.9"},{"seq":109009,"id":"CVE-2026-89478","ts":1789183729939,"field":"severity","old":"none","new":"medium"}]}