CVE-2026-52924
Estado: ModificadaCrítica (9.8)—
In the Linux kernel, the following vulnerability has been resolved:
sctp: purge outqueue on stale COOKIE-ECHO handling
sctp_stream_update() is only invoked when the association is moved into COOKIE_WAIT during association setup/reconfiguration. In this path, the outbound stream scheduler state (stream->out_curr) is expected to be clean, since no user data should have been transmitted yet unless the state machine has already partially progressed.
However, a corner case exists in sctp_sf_do_5_2_6_stale(): when a Stale Cookie ERROR is received, the association is rolled back from COOKIE_ECHOED to COOKIE_WAIT. In this scenario, user data may already have been queued and even bundled with the COOKIE-ECHO chunk.
Leer descripción completaMostrar menos
During the rollback, sctp_stream_update() frees the old stream table and installs a new one, but it does not invalidate stream->out_curr. As a result, out_curr may still point to a freed sctp_stream_out entry from the previous stream state.
Later, SCTP scheduler dequeue paths (FCFS, RR, PRIO, etc.) rely on stream->out_curr->ext, which can lead to use-after-free once the old stream state has been released via sctp_stream_free().
This results in crashes such as (reported by Yuqi):
Fix this by fully purging the association outqueue when handling the Stale Cookie case. This ensures all pending transmit and retransmit state is dropped, and any scheduler cached pointers are invalidated, making it safe to rebuild stream state during COOKIE_WAIT restart.
Updating only stream->out_curr would be insufficient, since queued and retransmittable data would still reference the old stream state and trigger later use-after-free in dequeue paths.
Detalles técnicos trazas, registros y código del informe original
BUG: KASAN: slab-use-after-free in sctp_sched_fcfs_dequeue+0x13a/0x140
Read of size 8 at addr ff1100004d4d3208 by task mini_poc/9312
CPU: 1 UID: 1001 PID: 9312 Comm: mini_poc Not tainted
7.1.0-rc1-00305-gbd3a4795d574 #5 PREEMPT(full)
sctp_sched_fcfs_dequeue+0x13a/0x140
sctp_outq_flush+0x1603/0x33e0
sctp_do_sm+0x31c9/0x5d30
sctp_assoc_bh_rcv+0x392/0x6f0
sctp_inq_push+0x1db/0x270
sctp_rcv+0x138d/0x3c10CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 9.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.53%
- Percentil entre todas las CVEs puntuadas: 43
- Fecha de la puntuación: 5/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1190Exploit Public-Facing Applicationinitial access75 % - Impacto principal
T1499.004Application or System Exploitationimpact85 %
Vulnerabilidad remota (AV:N, PR:N, UI:N) en kernel Linux explotable sin autenticación. Use-after-free causa crash (DoS) y potencial escalada de privilegios por lectura/escritura en memoria kernel.
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
CWE
- CWE-416
- CWE-825
Referencias
- https://git.kernel.org/stable/c/1d4652f677906a64487c13f9ace54b0eb263b5d0
- https://git.kernel.org/stable/c/2afc9e684dc7fecf73db1edc937ebbc47b4b68dc
- https://git.kernel.org/stable/c/3c0741a441a7df7099d7ca6a64a6a0de09c677c8
- https://git.kernel.org/stable/c/83ade59e5da365f4bf8bce72c5a38774202b442f
- https://git.kernel.org/stable/c/84b7a319105db2f917ccdcf502bdc866082b1285
- https://git.kernel.org/stable/c/a6207349e703cfc04756a4d16dec9176135813a5
- https://git.kernel.org/stable/c/e374b22e9b07b72a25909621464ff74096151bfb
- https://git.kernel.org/stable/c/f46e1d1a758878f0d22c4fbbd1bf42bb7165d1e8
- https://access.redhat.com/errata/RHSA-2026:59723
- https://access.redhat.com/errata/RHSA-2026:59737
- https://access.redhat.com/errata/RHSA-2026:59821
- https://access.redhat.com/errata/RHSA-2026:67471
- https://access.redhat.com/security/cve/CVE-2026-52924
- https://bugzilla.redhat.com/show_bug.cgi?id=2492095
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52924.json
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-52924",
"cveTags": [],
"metrics": {
"cvssMetricV31": [
{
"type": "Secondary",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 9.8,
"attackVector": "NETWORK",
"baseSeverity": "CRITICAL",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.9,
"exploitabilityScore": 3.9
},
{
"type": "Secondary",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 8.8,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.9,
"exploitabilityScore": 2.8
}
]
},
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5bbbbe32a43199c2b9ea5ea66fab6241c64beb51",
"lessThan": "84b7a319105db2f917ccdcf502bdc866082b1285",
"versionType": "git"
},
{
"status": "affected",
"version": "5bbbbe32a43199c2b9ea5ea66fab6241c64beb51",
"lessThan": "f46e1d1a758878f0d22c4fbbd1bf42bb7165d1e8",
"versionType": "git"
},
{
"status": "affected",
"version": "5bbbbe32a43199c2b9ea5ea66fab6241c64beb51",
"lessThan": "3c0741a441a7df7099d7ca6a64a6a0de09c677c8",
"versionType": "git"
},
{
"status": "affected",
"version": "5bbbbe32a43199c2b9ea5ea66fab6241c64beb51",
"lessThan": "2afc9e684dc7fecf73db1edc937ebbc47b4b68dc",
"versionType": "git"
},
{
"status": "affected",
"version": "5bbbbe32a43199c2b9ea5ea66fab6241c64beb51",
"lessThan": "1d4652f677906a64487c13f9ace54b0eb263b5d0",
"versionType": "git"
},
{
"status": "affected",
"version": "5bbbbe32a43199c2b9ea5ea66fab6241c64beb51",
"lessThan": "a6207349e703cfc04756a4d16dec9176135813a5",
"versionType": "git"
},
{
"status": "affected",
"version": "5bbbbe32a43199c2b9ea5ea66fab6241c64beb51",
"lessThan": "83ade59e5da365f4bf8bce72c5a38774202b442f",
"versionType": "git"
},
{
"status": "affected",
"version": "5bbbbe32a43199c2b9ea5ea66fab6241c64beb51",
"lessThan": "e374b22e9b07b72a25909621464ff74096151bfb",
"versionType": "git"
}
],
"programFiles": [
"net/sctp/sm_statefuns.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "4.15"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "4.15",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.259",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.210",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.176",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.143",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.94",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.36",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.0.13",
"versionType": "semver",
"lessThanOrEqual": "7.0.*"
},
{
"status": "unaffected",
"version": "7.1",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/sctp/sm_statefuns.c"
],
"defaultStatus": "affected"
}
]
},
{
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"affectedData": [
{
"cpes": [
"cpe:/a:redhat:enterprise_linux:8::nfv"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 8",
"versions": [
{
"status": "unaffected",
"version": "0:4.18.0-553.158.1.rt7.499.el8_10",
"lessThan": "*",
"versionType": "rpm"
}
],
"packageName": "kernel-rt",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/o:redhat:enterprise_linux:8"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 8",
"versions": [
{
"status": "unaffected",
"version": "0:4.18.0-553.158.1.el8_10",
"lessThan": "*",
"versionType": "rpm"
}
],
"packageName": "kernel",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/a:redhat:enterprise_linux:9",
"cpe:/o:redhat:enterprise_linux:9"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 9",
"versions": [
{
"status": "unaffected",
"version": "0:5.14.0-687.42.1.el9_8",
"lessThan": "*",
"versionType": "rpm"
}
],
"packageName": "kernel",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/o:redhat:enterprise_linux:10"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 10",
"packageName": "kernel",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/o:redhat:enterprise_linux:6"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 6",
"packageName": "kernel",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "unaffected"
},
{
"cpes": [
"cpe:/o:redhat:enterprise_linux:7"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 7",
"packageName": "kernel",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "unaffected"
},
{
"cpes": [
"cpe:/o:redhat:enterprise_linux:7"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 7",
"packageName": "kernel-rt",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "unaffected"
},
{
"cpes": [
"cpe:/o:redhat:enterprise_linux:9"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 9",
"packageName": "kernel-rt",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
}
]
}
],
"published": "2026-06-24T08:16:22.430",
"references": [
{
"url": "https://git.kernel.org/stable/c/1d4652f677906a64487c13f9ace54b0eb263b5d0",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/2afc9e684dc7fecf73db1edc937ebbc47b4b68dc",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/3c0741a441a7df7099d7ca6a64a6a0de09c677c8",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/83ade59e5da365f4bf8bce72c5a38774202b442f",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/84b7a319105db2f917ccdcf502bdc866082b1285",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/a6207349e703cfc04756a4d16dec9176135813a5",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/e374b22e9b07b72a25909621464ff74096151bfb",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/f46e1d1a758878f0d22c4fbbd1bf42bb7165d1e8",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://access.redhat.com/errata/RHSA-2026:59723",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://access.redhat.com/errata/RHSA-2026:59737",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://access.redhat.com/errata/RHSA-2026:59821",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://access.redhat.com/errata/RHSA-2026:67471",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://access.redhat.com/security/cve/CVE-2026-52924",
"tags": [
"Third Party Advisory"
],
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2492095",
"tags": [
"Issue Tracking",
"Third Party Advisory"
],
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52924.json",
"tags": [
"Third Party Advisory"
],
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
}
],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "CWE-416"
}
]
},
{
"type": "Secondary",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"description": [
{
"lang": "en",
"value": "CWE-825"
}
]
}
],
"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."
}
],
"lastModified": "2026-09-15T12:17:51.013",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "E2E6634B-DED7-40B3-A18B-2140A791419F",
"versionEndExcluding": "5.10.259",
"versionStartIncluding": "4.15"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "5E938CDF-D1C4-43D0-98DC-9E11B6B55801",
"versionEndExcluding": "5.15.210",
"versionStartIncluding": "5.11"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "C4446623-5F2B-4DD8-8666-9FAAC285A757",
"versionEndExcluding": "6.1.176",
"versionStartIncluding": "5.16"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "9062F1CD-CAD6-4EA2-A73F-C06D4A887B8C",
"versionEndExcluding": "6.6.143",
"versionStartIncluding": "6.2"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "85421C0C-ABDE-4357-971C-67F9087DE1B9",
"versionEndExcluding": "6.12.94",
"versionStartIncluding": "6.7"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "389025D2-958D-41BD-BD96-70ED1033A9F3",
"versionEndExcluding": "6.18.36",
"versionStartIncluding": "6.13"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "6A64BF9F-3BCA-42FD-98CB-8F03474D2B1E",
"versionEndExcluding": "7.0.13",
"versionStartIncluding": "6.19"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "B1EF7059-E670-45F4-B422-54C40FA86390"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "0D38F0BF-A728-4133-A358-D44A2F7EE6D6"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "EC732D08-5F7B-46D9-B154-E60C7F4F0A97"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "E5910A9D-F60A-409A-B486-FE66BFEBA9B9"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "81DFF19E-9CF8-49C6-8C36-1E4038622933"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "B0E8FC71-3952-444C-83E9-718DBBBEC615"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}