CVE-2026-74255: Linux kernel · tipc: fix UAF in tipc_l2_send_msg()
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 9.8 Critical · fixed in 5.15.0-1117.124~20.04.1 : patch Linux kernel as a priority.
Data as of 26 Oct 2026, 12:55 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 42% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.15.0-1117.124~20.04.1, 5.15.0-1123.132~20.04.1, 5.15.0-1122.131~20.04.1 +43
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 15 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A patch is available and should be applied to affected Linux kernel versions immediately. The fix involves clearing the media_ptr before calling synchronize_net() to prevent use-after-free conditions. Users should update to patched linux-aws kernel versions listed in the advisory. No alternative mitigations are indicated by the vendor advisory.
Description
A use-after-free vulnerability was identified and fixed in the Linux kernel's TIPC subsystem, specifically in the tipc_l2_send_msg() function. The flaw involved improper synchronization leading to a device pointer being freed while still in use by concurrent readers. This could allow an attacker to cause memory corruption. The issue has been patched in affected Linux kernel versions. The vulnerability has a high CVSS score of 9.8, indicating critical impact on confidentiality, integrity, and availability.
References
- nvd.nist.gov/vuln/detail/CVE-2026-74255 (opens in a new tab)
- git.kernel.org/stable/c/0d8a12d7143126afdf9fbe2e3d438650dd6603ed (opens in a new tab)
- git.kernel.org/stable/c/35e0297a93c3c34a3924eeef816c03504e3ab5c5 (opens in a new tab)
- git.kernel.org/stable/c/50ff092633b06382e5091dd5b093ce943d4ac2f9 (opens in a new tab)
- git.kernel.org/stable/c/609ced2301be1df7e7ed2ef47d1d916674e6ba3b (opens in a new tab)
- git.kernel.org/stable/c/71aafa16d79b107b33837f60b6cbc7d0cb8c5708 (opens in a new tab)
- git.kernel.org/stable/c/aef12b5ce793dea6b3a97a58fd0f946000ae8945 (opens in a new tab)
- git.kernel.org/stable/c/f4002f1c669cc02e3763f479fc25ff1dfa9e2420 (opens in a new tab)
- git.kernel.org/stable/c/f4c3d89fc986b0da196ddfc6cfe0ea5d5d08bec6 (opens in a new tab)
- ubuntu.com/security/CVE-2026-74255 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-74255 (opens in a new tab)
- git.kernel.org/linus/f4c3d89fc986b0da196ddfc6cfe0ea5d5d08bec6 (opens in a new tab)
- ubuntu.com/security/notices/USN-8781-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8816-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8876-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8878-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8879-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8877-1 (opens in a new tab)