{"apiVersion":"1.0","identifier":"CVE-2026-74587","description":"In the Linux kernel, the following vulnerability has been resolved: sctp: fix use-after-free of cached ASCONF chunk addip_last_asconf caches the outstanding outbound ASCONF chunk. The normal ASCONF-ACK completion path releases the chunk and clears the pointer. However, sctp_asconf_queue_teardown() releases the cached chunk without clearing addip_last_asconf. During peer restart handling, sctp_sf_do_dupcook_a() queues SCTP_CMD_PURGE_ASCONF_QUEUE, which invokes sctp_asconf_queue_teardown() while the association remains alive and leaves the pointer dangling. A delayed authenticated ASCONF-ACK can then reach sctp_sf_do_asconf_ack(), which accesses the stale chunk and passes it to sctp_process_asconf_ack(), causing a use-after-free and a second release. Clearing the pointer exposes a race with T4 expiry. Peer restart handling queues the timer stop before the purge, but SCTP_CMD_TIMER_STOP uses timer_delete(), which does not wait for a callback already running on another CPU. Such a callback can reach sctp_sf_t4_timer_expire() after the purge and dereference NULL. Clear addip_last_asconf after releasing the cached chunk, and make sctp_sf_t4_timer_expire() consume a stale T4 expiry if no outstanding ASCONF remains.","publishedAt":"2026-08-22T16:16:30","lastModifiedAt":"2026-08-25T06:18:33","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-74587","cvssScore":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","epssProbability":0.005,"riskScore":1.02,"affectedProduct":"Linux kernel","affectedVersions":"unknown","vulnerabilityType":"Kernel","operatingSystems":[],"links":{"self":"https://www.redsauce.net/api/cves/CVE-2026-74587","webPages":{"es":"https://www.redsauce.net/es/cves/CVE-2026-74587","en":"https://www.redsauce.net/en/cves/CVE-2026-74587","fr":"https://www.redsauce.net/fr/cves/CVE-2026-74587","pt":"https://www.redsauce.net/pt/cves/CVE-2026-74587","de":"https://www.redsauce.net/de/cves/CVE-2026-74587","sk":"https://www.redsauce.net/sk/cves/CVE-2026-74587","el":"https://www.redsauce.net/el/cves/CVE-2026-74587"},"source":"https://nvd.nist.gov/vuln/detail/CVE-2026-74587"}}