{"api_version":"1","generated_at":"2026-06-25T03:16:59+00:00","cve":"CVE-2026-52924","urls":{"html":"https://cve.report/CVE-2026-52924","api":"https://cve.report/api/cve/CVE-2026-52924.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-52924","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-52924"},"summary":{"title":"sctp: purge outqueue on stale COOKIE-ECHO handling","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: purge outqueue on stale COOKIE-ECHO handling\n\nsctp_stream_update() is only invoked when the association is moved into\nCOOKIE_WAIT during association setup/reconfiguration. In this path, the\noutbound stream scheduler state (stream->out_curr) is expected to be\nclean, since no user data should have been transmitted yet unless the\nstate machine has already partially progressed.\n\nHowever, a corner case exists in sctp_sf_do_5_2_6_stale(): when a\nStale Cookie ERROR is received, the association is rolled back from\nCOOKIE_ECHOED to COOKIE_WAIT. In this scenario, user data may already\nhave been queued and even bundled with the COOKIE-ECHO chunk.\n\nDuring the rollback, sctp_stream_update() frees the old stream table\nand installs a new one, but it does not invalidate stream->out_curr.\nAs a result, out_curr may still point to a freed sctp_stream_out\nentry from the previous stream state.\n\nLater, SCTP scheduler dequeue paths (FCFS, RR, PRIO, etc.) rely on\nstream->out_curr->ext, which can lead to use-after-free once the old\nstream state has been released via sctp_stream_free().\n\nThis results in crashes such as (reported by Yuqi):\n\n  BUG: KASAN: slab-use-after-free in sctp_sched_fcfs_dequeue+0x13a/0x140\n  Read of size 8 at addr ff1100004d4d3208 by task mini_poc/9312\n  CPU: 1 UID: 1001 PID: 9312 Comm: mini_poc Not tainted\n     7.1.0-rc1-00305-gbd3a4795d574 #5 PREEMPT(full)\n   sctp_sched_fcfs_dequeue+0x13a/0x140\n   sctp_outq_flush+0x1603/0x33e0\n   sctp_do_sm+0x31c9/0x5d30\n   sctp_assoc_bh_rcv+0x392/0x6f0\n   sctp_inq_push+0x1db/0x270\n   sctp_rcv+0x138d/0x3c10\n\nFix this by fully purging the association outqueue when handling the\nStale Cookie case. This ensures all pending transmit and retransmit\nstate is dropped, and any scheduler cached pointers are invalidated,\nmaking it safe to rebuild stream state during COOKIE_WAIT restart.\n\nUpdating only stream->out_curr would be insufficient, since queued\nand retransmittable data would still reference the old stream state and\ntrigger later use-after-free in dequeue paths.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-06-24 08:16:22","updated_at":"2026-06-24 08:16:22"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/83ade59e5da365f4bf8bce72c5a38774202b442f","name":"https://git.kernel.org/stable/c/83ade59e5da365f4bf8bce72c5a38774202b442f","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/a6207349e703cfc04756a4d16dec9176135813a5","name":"https://git.kernel.org/stable/c/a6207349e703cfc04756a4d16dec9176135813a5","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/84b7a319105db2f917ccdcf502bdc866082b1285","name":"https://git.kernel.org/stable/c/84b7a319105db2f917ccdcf502bdc866082b1285","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/e374b22e9b07b72a25909621464ff74096151bfb","name":"https://git.kernel.org/stable/c/e374b22e9b07b72a25909621464ff74096151bfb","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/1d4652f677906a64487c13f9ace54b0eb263b5d0","name":"https://git.kernel.org/stable/c/1d4652f677906a64487c13f9ace54b0eb263b5d0","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/f46e1d1a758878f0d22c4fbbd1bf42bb7165d1e8","name":"https://git.kernel.org/stable/c/f46e1d1a758878f0d22c4fbbd1bf42bb7165d1e8","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/2afc9e684dc7fecf73db1edc937ebbc47b4b68dc","name":"https://git.kernel.org/stable/c/2afc9e684dc7fecf73db1edc937ebbc47b4b68dc","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/3c0741a441a7df7099d7ca6a64a6a0de09c677c8","name":"https://git.kernel.org/stable/c/3c0741a441a7df7099d7ca6a64a6a0de09c677c8","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-52924","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-52924","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5bbbbe32a43199c2b9ea5ea66fab6241c64beb51 84b7a319105db2f917ccdcf502bdc866082b1285 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5bbbbe32a43199c2b9ea5ea66fab6241c64beb51 f46e1d1a758878f0d22c4fbbd1bf42bb7165d1e8 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5bbbbe32a43199c2b9ea5ea66fab6241c64beb51 3c0741a441a7df7099d7ca6a64a6a0de09c677c8 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5bbbbe32a43199c2b9ea5ea66fab6241c64beb51 2afc9e684dc7fecf73db1edc937ebbc47b4b68dc git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5bbbbe32a43199c2b9ea5ea66fab6241c64beb51 1d4652f677906a64487c13f9ace54b0eb263b5d0 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5bbbbe32a43199c2b9ea5ea66fab6241c64beb51 a6207349e703cfc04756a4d16dec9176135813a5 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5bbbbe32a43199c2b9ea5ea66fab6241c64beb51 83ade59e5da365f4bf8bce72c5a38774202b442f git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5bbbbe32a43199c2b9ea5ea66fab6241c64beb51 e374b22e9b07b72a25909621464ff74096151bfb git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4.15","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 4.15 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.10.259 5.10.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.15.210 5.15.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.176 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.143 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.94 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.36 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0.13 7.0.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"52924","cve":"CVE-2026-52924","epss":"0.001650000","percentile":"0.059900000","score_date":"2026-06-24","updated_at":"2026-06-25 00:05:27"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/sctp/sm_statefuns.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"84b7a319105db2f917ccdcf502bdc866082b1285","status":"affected","version":"5bbbbe32a43199c2b9ea5ea66fab6241c64beb51","versionType":"git"},{"lessThan":"f46e1d1a758878f0d22c4fbbd1bf42bb7165d1e8","status":"affected","version":"5bbbbe32a43199c2b9ea5ea66fab6241c64beb51","versionType":"git"},{"lessThan":"3c0741a441a7df7099d7ca6a64a6a0de09c677c8","status":"affected","version":"5bbbbe32a43199c2b9ea5ea66fab6241c64beb51","versionType":"git"},{"lessThan":"2afc9e684dc7fecf73db1edc937ebbc47b4b68dc","status":"affected","version":"5bbbbe32a43199c2b9ea5ea66fab6241c64beb51","versionType":"git"},{"lessThan":"1d4652f677906a64487c13f9ace54b0eb263b5d0","status":"affected","version":"5bbbbe32a43199c2b9ea5ea66fab6241c64beb51","versionType":"git"},{"lessThan":"a6207349e703cfc04756a4d16dec9176135813a5","status":"affected","version":"5bbbbe32a43199c2b9ea5ea66fab6241c64beb51","versionType":"git"},{"lessThan":"83ade59e5da365f4bf8bce72c5a38774202b442f","status":"affected","version":"5bbbbe32a43199c2b9ea5ea66fab6241c64beb51","versionType":"git"},{"lessThan":"e374b22e9b07b72a25909621464ff74096151bfb","status":"affected","version":"5bbbbe32a43199c2b9ea5ea66fab6241c64beb51","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/sctp/sm_statefuns.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"4.15"},{"lessThan":"4.15","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"5.10.*","status":"unaffected","version":"5.10.259","versionType":"semver"},{"lessThanOrEqual":"5.15.*","status":"unaffected","version":"5.15.210","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.176","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.143","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.94","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.36","versionType":"semver"},{"lessThanOrEqual":"7.0.*","status":"unaffected","version":"7.0.13","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.10.259","versionStartIncluding":"4.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.15.210","versionStartIncluding":"4.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.176","versionStartIncluding":"4.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.143","versionStartIncluding":"4.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.94","versionStartIncluding":"4.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.36","versionStartIncluding":"4.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0.13","versionStartIncluding":"4.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1","versionStartIncluding":"4.15","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: purge outqueue on stale COOKIE-ECHO handling\n\nsctp_stream_update() is only invoked when the association is moved into\nCOOKIE_WAIT during association setup/reconfiguration. In this path, the\noutbound stream scheduler state (stream->out_curr) is expected to be\nclean, since no user data should have been transmitted yet unless the\nstate machine has already partially progressed.\n\nHowever, a corner case exists in sctp_sf_do_5_2_6_stale(): when a\nStale Cookie ERROR is received, the association is rolled back from\nCOOKIE_ECHOED to COOKIE_WAIT. In this scenario, user data may already\nhave been queued and even bundled with the COOKIE-ECHO chunk.\n\nDuring the rollback, sctp_stream_update() frees the old stream table\nand installs a new one, but it does not invalidate stream->out_curr.\nAs a result, out_curr may still point to a freed sctp_stream_out\nentry from the previous stream state.\n\nLater, SCTP scheduler dequeue paths (FCFS, RR, PRIO, etc.) rely on\nstream->out_curr->ext, which can lead to use-after-free once the old\nstream state has been released via sctp_stream_free().\n\nThis results in crashes such as (reported by Yuqi):\n\n  BUG: KASAN: slab-use-after-free in sctp_sched_fcfs_dequeue+0x13a/0x140\n  Read of size 8 at addr ff1100004d4d3208 by task mini_poc/9312\n  CPU: 1 UID: 1001 PID: 9312 Comm: mini_poc Not tainted\n     7.1.0-rc1-00305-gbd3a4795d574 #5 PREEMPT(full)\n   sctp_sched_fcfs_dequeue+0x13a/0x140\n   sctp_outq_flush+0x1603/0x33e0\n   sctp_do_sm+0x31c9/0x5d30\n   sctp_assoc_bh_rcv+0x392/0x6f0\n   sctp_inq_push+0x1db/0x270\n   sctp_rcv+0x138d/0x3c10\n\nFix this by fully purging the association outqueue when handling the\nStale Cookie case. This ensures all pending transmit and retransmit\nstate is dropped, and any scheduler cached pointers are invalidated,\nmaking it safe to rebuild stream state during COOKIE_WAIT restart.\n\nUpdating only stream->out_curr would be insufficient, since queued\nand retransmittable data would still reference the old stream state and\ntrigger later use-after-free in dequeue paths."}],"providerMetadata":{"dateUpdated":"2026-06-24T07:14:18.646Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/84b7a319105db2f917ccdcf502bdc866082b1285"},{"url":"https://git.kernel.org/stable/c/f46e1d1a758878f0d22c4fbbd1bf42bb7165d1e8"},{"url":"https://git.kernel.org/stable/c/3c0741a441a7df7099d7ca6a64a6a0de09c677c8"},{"url":"https://git.kernel.org/stable/c/2afc9e684dc7fecf73db1edc937ebbc47b4b68dc"},{"url":"https://git.kernel.org/stable/c/1d4652f677906a64487c13f9ace54b0eb263b5d0"},{"url":"https://git.kernel.org/stable/c/a6207349e703cfc04756a4d16dec9176135813a5"},{"url":"https://git.kernel.org/stable/c/83ade59e5da365f4bf8bce72c5a38774202b442f"},{"url":"https://git.kernel.org/stable/c/e374b22e9b07b72a25909621464ff74096151bfb"}],"title":"sctp: purge outqueue on stale COOKIE-ECHO handling","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-52924","datePublished":"2026-06-24T07:14:18.646Z","dateReserved":"2026-06-09T07:44:35.368Z","dateUpdated":"2026-06-24T07:14:18.646Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-06-24 08:16:22","lastModifiedDate":"2026-06-24 08:16:22","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"52924","Ordinal":"1","Title":"sctp: purge outqueue on stale COOKIE-ECHO handling","CVE":"CVE-2026-52924","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"52924","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: purge outqueue on stale COOKIE-ECHO handling\n\nsctp_stream_update() is only invoked when the association is moved into\nCOOKIE_WAIT during association setup/reconfiguration. In this path, the\noutbound stream scheduler state (stream->out_curr) is expected to be\nclean, since no user data should have been transmitted yet unless the\nstate machine has already partially progressed.\n\nHowever, a corner case exists in sctp_sf_do_5_2_6_stale(): when a\nStale Cookie ERROR is received, the association is rolled back from\nCOOKIE_ECHOED to COOKIE_WAIT. In this scenario, user data may already\nhave been queued and even bundled with the COOKIE-ECHO chunk.\n\nDuring the rollback, sctp_stream_update() frees the old stream table\nand installs a new one, but it does not invalidate stream->out_curr.\nAs a result, out_curr may still point to a freed sctp_stream_out\nentry from the previous stream state.\n\nLater, SCTP scheduler dequeue paths (FCFS, RR, PRIO, etc.) rely on\nstream->out_curr->ext, which can lead to use-after-free once the old\nstream state has been released via sctp_stream_free().\n\nThis results in crashes such as (reported by Yuqi):\n\n  BUG: KASAN: slab-use-after-free in sctp_sched_fcfs_dequeue+0x13a/0x140\n  Read of size 8 at addr ff1100004d4d3208 by task mini_poc/9312\n  CPU: 1 UID: 1001 PID: 9312 Comm: mini_poc Not tainted\n     7.1.0-rc1-00305-gbd3a4795d574 #5 PREEMPT(full)\n   sctp_sched_fcfs_dequeue+0x13a/0x140\n   sctp_outq_flush+0x1603/0x33e0\n   sctp_do_sm+0x31c9/0x5d30\n   sctp_assoc_bh_rcv+0x392/0x6f0\n   sctp_inq_push+0x1db/0x270\n   sctp_rcv+0x138d/0x3c10\n\nFix this by fully purging the association outqueue when handling the\nStale Cookie case. This ensures all pending transmit and retransmit\nstate is dropped, and any scheduler cached pointers are invalidated,\nmaking it safe to rebuild stream state during COOKIE_WAIT restart.\n\nUpdating only stream->out_curr would be insufficient, since queued\nand retransmittable data would still reference the old stream state and\ntrigger later use-after-free in dequeue paths.","Type":"Description","Title":"sctp: purge outqueue on stale COOKIE-ECHO handling"}]}}}