{"id":"CVE-2026-74587","revision":"003abe3907bf4b6796f29be5929f3093","records":[{"revision":"003abe3907bf4b6796f29be5929f3093","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-74587","aliases":[],"title":"sctp: fix use-after-free of cached ASCONF chunk","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: fix use-after-free of cached ASCONF chunk\n\naddip_last_asconf caches the outstanding outbound ASCONF chunk. The normal\nASCONF-ACK completion path releases the chunk and clears the pointer.\n\nHowever, sctp_asconf_queue_teardown() releases the cached chunk without\nclearing addip_last_asconf. During peer restart handling,\nsctp_sf_do_dupcook_a() queues SCTP_CMD_PURGE_ASCONF_QUEUE, which invokes\nsctp_asconf_queue_teardown() while the association remains alive and leaves\nthe pointer dangling.\n\nA delayed authenticated ASCONF-ACK can then reach sctp_sf_do_asconf_ack(),\nwhich accesses the stale chunk and passes it to sctp_process_asconf_ack(),\ncausing a use-after-free and a second release.\n\nClearing the pointer exposes a race with T4 expiry. Peer restart handling\nqueues the timer stop before the purge, but SCTP_CMD_TIMER_STOP uses\ntimer_delete(), which does not wait for a callback already running on\nanother CPU. Such a callback can reach sctp_sf_t4_timer_expire() after\nthe purge and dereference NULL.\n\nClear addip_last_asconf after releasing the cached chunk, and make\nsctp_sf_t4_timer_expire() consume a stale T4 expiry if no outstanding\nASCONF remains.","state":0,"publishedAt":"2026-08-22T15:31:39.81+00:00","modifiedAt":"2026-10-16T19:05:58.841+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/sctp/associola.c\",\n                        \"net/sctp/sm_statefuns.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"a000c01e60e40e15304ffe48fff051d17a7bea91\",\n                            \"lessThan\": \"10459b03e2d9ee12435e96f587de4d4cacdbf435\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a000c01e60e40e15304ffe48fff051d17a7bea91\",\n                            \"lessThan\": \"e1bb114e09372fd6e03387ced9ef566da336ed6c\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a000c01e60e40e15304ffe48fff051d17a7bea91\",\n                            \"lessThan\": \"179676f0166230c80053a392303485b37c93dd33\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a000c01e60e40e15304ffe48fff051d17a7bea91\",\n                            \"lessThan\": \"dc67d528c2fa939cec7fe3bf7f3089c8d281ca3d\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a000c01e60e40e15304ffe48fff051d17a7bea91\",\n                            \"lessThan\": \"618b5c6d049896fcfabb91afc072954c92cb2693\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a000c01e60e40e15304ffe48fff051d17a7bea91\",\n                            \"lessThan\": \"07daf4f9750104960a1d60831b2353c0d41f35fb\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a000c01e60e40e15304ffe48fff051d17a7bea91\",\n                            \"lessThan\": \"d949992bc3f00027a2c755e860a11950c75f6073\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a000c01e60e40e15304ffe48fff051d17a7bea91\",\n                            \"lessThan\": \"8c283e7b56adce00193837f3311b06662466fb21\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/sctp/associola.c\",\n                        \"net/sctp/sm_statefuns.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"3.0\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"3.0\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.265\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.216\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.183\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.152\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.104\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.45\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.1.9\",\n                            \"lessThanOrEqual\": \"7.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 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,"severity":"CRITICAL"}],"references":["https://git.kernel.org/stable/c/10459b03e2d9ee12435e96f587de4d4cacdbf435","https://git.kernel.org/stable/c/e1bb114e09372fd6e03387ced9ef566da336ed6c","https://git.kernel.org/stable/c/179676f0166230c80053a392303485b37c93dd33","https://git.kernel.org/stable/c/dc67d528c2fa939cec7fe3bf7f3089c8d281ca3d","https://git.kernel.org/stable/c/618b5c6d049896fcfabb91afc072954c92cb2693","https://git.kernel.org/stable/c/07daf4f9750104960a1d60831b2353c0d41f35fb","https://git.kernel.org/stable/c/d949992bc3f00027a2c755e860a11950c75f6073","https://git.kernel.org/stable/c/8c283e7b56adce00193837f3311b06662466fb21"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-74587","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-74587","identifiers":["CVE-2026-74587"]},"retained":false,"historicalAffected":[]}],"coverage":[]}