{"cve":"CVE-2026-74588","nvd":{"published":"2026-08-22T16:16:30.960","modified":"2026-10-16T20:17:42.177","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: keep chunk->transport in step with the list it is queued on\n\n__sctp_outq_flush_rtx() moves a gap-acked chunk onto another transport's\ntransmitted list without updating chunk->transport:\n\n\tif (chunk->tsn_gap_acked) {\n\t\tlist_move_tail(&chunk->transmitted_list,\n\t\t\t       &transport->transmitted);\n\t\tcontinue;\n\t}\n\nThe chunk then sits on a live transport's list while chunk->transport still\nnames a different one.  If that transport is removed - sctp_assoc_rm_peer()\nfrom an ASCONF Delete-IP - sctp_transport_free() RCU-frees it and the chunk\nis left with a dangling pointer.  sctp_assoc_rm_peer() scrubs\npeer->transmitted and asoc->outqueue.out_chunk_list, but the chunk is on\nneither.\n\nThe pointer is not followed while tsn_gap_acked is set.  A SACK that\nreneges on the TSN clears the flag, and the next SACK reaches\n\n\ttchunk->transport->flight_size -= sctp_data_size(tchunk);\n\ninside the freed transport.  KASAN reports a slab-use-after-free read in\nsctp_check_transmitted(), freed from sctp_assoc_rm_peer().  Both the\nremoval and the SACKs come from the association peer.\n\nSet chunk->transport at the move.  The ordinary resend path needs nothing:\nit reaches its list_move_tail() only after sctp_packet_append_chunk()\nreturned SCTP_XMIT_OK, and __sctp_packet_append_chunk() has rebound the\nchunk by then.\n\nDiscovered by XBOW, triaged by Baul Lee <baul.lee@xbow.com>","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8},"cwes":[],"references":["https://git.kernel.org/stable/c/1adf929121e13e0b19200bb9fef715b918d483fe","https://git.kernel.org/stable/c/2b3b5eec8b2c30ee237e3c31a6a38de9c39d804d","https://git.kernel.org/stable/c/5ccf35ef0ed6059cdf8b1f4606a6584d5b67166b","https://git.kernel.org/stable/c/6575fb17230814b48b471727c8410c0aadff9274","https://git.kernel.org/stable/c/6b9e2ea2057113f3393990ba646d2d97c719a80d"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:49:38.260478770+00:00"},"epss":{"cve":"CVE-2026-74588","score":0.005,"percentile":0.42523,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}