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9.8
CRITICAL CVSS 3.1
CVE-2026-52924
sctp: purge outqueue on stale COOKIE-ECHO handling
Overview
Description

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. 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): 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/0x3c10 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.

Details
INFO

Published Date :

June 24, 2026, 8:16 a.m.

Last Modified :

July 15, 2026, 1:16 a.m.

Remotely Exploit :

Yes !

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Impact
Affected Products

The following products are affected by CVE-2026-52924 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Linux linux_kernel
: Total Affected Vendor : 1 | Products : 1
Scoring
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 CRITICAL 416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS 3.1 HIGH 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
CVSS 3.1 HIGH 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Solution
Purge the association outqueue on stale COOKIE-ECHO handling to prevent use-after-free.
  • Update the Linux kernel to apply the fix.
  • Ensure all pending data and scheduler pointers are invalidated.
  • Rebuild stream state during COOKIE_WAIT restart.
References
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-52924.

URL Resource
https://git.kernel.org/stable/c/1d4652f677906a64487c13f9ace54b0eb263b5d0 Patch
https://git.kernel.org/stable/c/2afc9e684dc7fecf73db1edc937ebbc47b4b68dc Patch
https://git.kernel.org/stable/c/3c0741a441a7df7099d7ca6a64a6a0de09c677c8 Patch
https://git.kernel.org/stable/c/83ade59e5da365f4bf8bce72c5a38774202b442f Patch
https://git.kernel.org/stable/c/84b7a319105db2f917ccdcf502bdc866082b1285 Patch
https://git.kernel.org/stable/c/a6207349e703cfc04756a4d16dec9176135813a5 Patch
https://git.kernel.org/stable/c/e374b22e9b07b72a25909621464ff74096151bfb Patch
https://git.kernel.org/stable/c/f46e1d1a758878f0d22c4fbbd1bf42bb7165d1e8 Patch
https://access.redhat.com/security/cve/CVE-2026-52924 Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2492095 Issue Tracking Third Party Advisory
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52924.json Third Party Advisory
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-52924 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-52924 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-52924 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2026-52924 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

    Jul. 15, 2026

    Action Type Old Value New Value
    Changed Affected [{'cpes': ['cpe:/o:redhat:enterprise_linux:10'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 10', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:8'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 8', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:9'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 9', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:6'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 6', 'defaultStatus': 'unaffected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:7'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 7', 'defaultStatus': 'unaffected'}] [{'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:8'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 8', 'packageName': 'kernel', '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', 'packageName': 'kernel-rt', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:9'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 9', 'packageName': 'kernel', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'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'}]
  • CVE Modified by 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

    Jul. 10, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H
    Removed CVSS V3.1 AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
  • Initial Analysis by [email protected]

    Jul. 08, 2026

    Action Type Old Value New Value
    Added CWE CWE-416
    Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.16 up to (excluding) 6.1.176 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.2 up to (excluding) 6.6.143 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.11 up to (excluding) 5.15.210 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.13 up to (excluding) 6.18.36 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.7 up to (excluding) 6.12.94 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.19 up to (excluding) 7.0.13 *cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.15 up to (excluding) 5.10.259
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/1d4652f677906a64487c13f9ace54b0eb263b5d0 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/2afc9e684dc7fecf73db1edc937ebbc47b4b68dc Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/3c0741a441a7df7099d7ca6a64a6a0de09c677c8 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/83ade59e5da365f4bf8bce72c5a38774202b442f Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/84b7a319105db2f917ccdcf502bdc866082b1285 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/a6207349e703cfc04756a4d16dec9176135813a5 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/e374b22e9b07b72a25909621464ff74096151bfb Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/f46e1d1a758878f0d22c4fbbd1bf42bb7165d1e8 Types: Patch
    Added Reference Type redhat-SADP: https://access.redhat.com/security/cve/CVE-2026-52924 Types: Third Party Advisory
    Added Reference Type redhat-SADP: https://bugzilla.redhat.com/show_bug.cgi?id=2492095 Types: Issue Tracking, Third Party Advisory
    Added Reference Type redhat-SADP: https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52924.json Types: Third Party Advisory
  • CVE Modified by 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

    Jun. 30, 2026

    Action Type Old Value New Value
    Added Affected [{'cpes': ['cpe:/o:redhat:enterprise_linux:10'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 10', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:8'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 8', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:9'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 9', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:6'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 6', 'defaultStatus': 'unaffected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:7'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 7', 'defaultStatus': 'unaffected'}]
    Added CVSS V3.1 AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-825
    Added Reference https://access.redhat.com/security/cve/CVE-2026-52924
    Added Reference https://bugzilla.redhat.com/show_bug.cgi?id=2492095
    Added Reference https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52924.json
  • CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Jun. 28, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Jun. 24, 2026

    Action Type Old Value New Value
    Added Affected [{'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'}]
    Added Description 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. 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): 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/0x3c10 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.
    Added Reference https://git.kernel.org/stable/c/1d4652f677906a64487c13f9ace54b0eb263b5d0
    Added Reference https://git.kernel.org/stable/c/2afc9e684dc7fecf73db1edc937ebbc47b4b68dc
    Added Reference https://git.kernel.org/stable/c/3c0741a441a7df7099d7ca6a64a6a0de09c677c8
    Added Reference https://git.kernel.org/stable/c/83ade59e5da365f4bf8bce72c5a38774202b442f
    Added Reference https://git.kernel.org/stable/c/84b7a319105db2f917ccdcf502bdc866082b1285
    Added Reference https://git.kernel.org/stable/c/a6207349e703cfc04756a4d16dec9176135813a5
    Added Reference https://git.kernel.org/stable/c/e374b22e9b07b72a25909621464ff74096151bfb
    Added Reference https://git.kernel.org/stable/c/f46e1d1a758878f0d22c4fbbd1bf42bb7165d1e8
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CVSS
Vulnerability Scoring Details
Base CVSS Score: 9.8
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact