9.8
CRITICAL
CVSS 3.1
CVE-2026-74255
tipc: fix UAF in tipc_l2_send_msg()
Overview
Description
In the Linux kernel, the following vulnerability has been resolved: tipc: fix UAF in tipc_l2_send_msg() Syzbot reported a slab-use-after-free in ipvlan_hard_header() when called from tipc_l2_send_msg(). The root cause is that tipc_disable_l2_media() calls synchronize_net() while b->media_ptr is still valid. This allows concurrent RCU readers to obtain the device pointer after synchronize_net() has finished. The pointer is cleared later in bearer_disable(), but without any subsequent synchronization, allowing the device to be freed while still in use by readers. Fix this by clearing b->media_ptr in tipc_disable_l2_media() before calling synchronize_net(). This is safe to do now because the call order in bearer_disable() was reversed in 0d051bf93c06 ("tipc: make bearer packet filtering generic") to call tipc_node_delete_links() (which needs the pointer) before disable_media(). https: //lore.kernel.org/netdev/[email protected]/T/#u
Details
INFO
Published Date :
Aug. 15, 2026, 6:22 a.m.
Last Modified :
Aug. 17, 2026, 6:19 a.m.
Remotely Exploit :
Yes !
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
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 |
Solution
Fix slab-use-after-free by clearing media pointer before synchronization.
- Clear b->media_ptr in tipc_disable_l2_media before synchronize_net.
- Apply the kernel patch that resolves this issue.
- Update the Linux kernel to a patched version.
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-2026-74255.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-74255 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-2026-74255
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-2026-74255 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-74255 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 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 17, 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 Changed Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': '609ced2301be1df7e7ed2ef47d1d916674e6ba3b', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': '71aafa16d79b107b33837f60b6cbc7d0cb8c5708', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': 'f4002f1c669cc02e3763f479fc25ff1dfa9e2420', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': '50ff092633b06382e5091dd5b093ce943d4ac2f9', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': 'aef12b5ce793dea6b3a97a58fd0f946000ae8945', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': '0d8a12d7143126afdf9fbe2e3d438650dd6603ed', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': '35e0297a93c3c34a3924eeef816c03504e3ab5c5', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': 'f4c3d89fc986b0da196ddfc6cfe0ea5d5d08bec6', 'versionType': 'git'}], 'programFiles': ['net/tipc/bearer.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.4'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.4', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.10.261', 'versionType': 'semver', 'lessThanOrEqual': '5.10.*'}, {'status': 'unaffected', 'version': '5.15.212', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.178', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.97', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.40', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/tipc/bearer.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': '609ced2301be1df7e7ed2ef47d1d916674e6ba3b', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': '71aafa16d79b107b33837f60b6cbc7d0cb8c5708', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': 'f4002f1c669cc02e3763f479fc25ff1dfa9e2420', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': '50ff092633b06382e5091dd5b093ce943d4ac2f9', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': 'aef12b5ce793dea6b3a97a58fd0f946000ae8945', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': '0d8a12d7143126afdf9fbe2e3d438650dd6603ed', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': '35e0297a93c3c34a3924eeef816c03504e3ab5c5', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': 'f4c3d89fc986b0da196ddfc6cfe0ea5d5d08bec6', 'versionType': 'git'}], 'programFiles': ['net/tipc/bearer.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.4'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.4', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.10.261', 'versionType': 'semver', 'lessThanOrEqual': '5.10.*'}, {'status': 'unaffected', 'version': '5.15.212', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.178', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.97', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.40', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/tipc/bearer.c'], 'defaultStatus': 'affected'}] -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 15, 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': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': '609ced2301be1df7e7ed2ef47d1d916674e6ba3b', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': '71aafa16d79b107b33837f60b6cbc7d0cb8c5708', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': 'f4002f1c669cc02e3763f479fc25ff1dfa9e2420', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': '50ff092633b06382e5091dd5b093ce943d4ac2f9', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': 'aef12b5ce793dea6b3a97a58fd0f946000ae8945', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': '0d8a12d7143126afdf9fbe2e3d438650dd6603ed', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': '35e0297a93c3c34a3924eeef816c03504e3ab5c5', 'versionType': 'git'}, {'status': 'affected', 'version': '282b3a056225b35024246f63feb91d769d714dad', 'lessThan': 'f4c3d89fc986b0da196ddfc6cfe0ea5d5d08bec6', 'versionType': 'git'}], 'programFiles': ['net/tipc/bearer.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.4'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.4', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.10.261', 'versionType': 'semver', 'lessThanOrEqual': '5.10.*'}, {'status': 'unaffected', 'version': '5.15.212', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.178', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.97', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.40', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/tipc/bearer.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: tipc: fix UAF in tipc_l2_send_msg() Syzbot reported a slab-use-after-free in ipvlan_hard_header() when called from tipc_l2_send_msg(). The root cause is that tipc_disable_l2_media() calls synchronize_net() while b->media_ptr is still valid. This allows concurrent RCU readers to obtain the device pointer after synchronize_net() has finished. The pointer is cleared later in bearer_disable(), but without any subsequent synchronization, allowing the device to be freed while still in use by readers. Fix this by clearing b->media_ptr in tipc_disable_l2_media() before calling synchronize_net(). This is safe to do now because the call order in bearer_disable() was reversed in 0d051bf93c06 ("tipc: make bearer packet filtering generic") to call tipc_node_delete_links() (which needs the pointer) before disable_media(). https: //lore.kernel.org/netdev/[email protected]/T/#u Added Reference https://git.kernel.org/stable/c/0d8a12d7143126afdf9fbe2e3d438650dd6603ed Added Reference https://git.kernel.org/stable/c/35e0297a93c3c34a3924eeef816c03504e3ab5c5 Added Reference https://git.kernel.org/stable/c/50ff092633b06382e5091dd5b093ce943d4ac2f9 Added Reference https://git.kernel.org/stable/c/609ced2301be1df7e7ed2ef47d1d916674e6ba3b Added Reference https://git.kernel.org/stable/c/71aafa16d79b107b33837f60b6cbc7d0cb8c5708 Added Reference https://git.kernel.org/stable/c/aef12b5ce793dea6b3a97a58fd0f946000ae8945 Added Reference https://git.kernel.org/stable/c/f4002f1c669cc02e3763f479fc25ff1dfa9e2420 Added Reference https://git.kernel.org/stable/c/f4c3d89fc986b0da196ddfc6cfe0ea5d5d08bec6
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.