CVE-2025-38403: Linux kernel · vsock/vmci: Clear the vmci transport packet properly when initializing it
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 5.15.0-1092.99~20.04.1 : patch Linux kernel soon.
Data as of 28 Oct 2026, 11:28 UTC
- Patch
- Available – fixed in 5.15.0-1092.99~20.04.1, 5.15.0-1096.105~20.04.1, 5.15.0-1092.101~20.04.1 +63
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 25 Jul 2025
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.
Patches and advisories
- ubuntu.com/security/notices/USN-7774-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7775-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7776-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7775-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7775-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-7833-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7834-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7833-2 (opens in a new tab)
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-aws-6.14pkg:deb/ubuntu/linux-aws-6.14?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azure-6.11pkg:deb/ubuntu/linux-azure-6.11?arch=source&distro=nobleOther 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 by upgrading to one of the fixed Linux kernel versions listed in the Ubuntu advisory USN-7774-1, including versions 5.15.0-1092.99~20.04.1 and later. Applying these official kernel updates fully mitigates the vulnerability. No additional mitigations are required beyond installing the fixed kernel versions.
Description
A vulnerability in the Linux kernel's vsock/vmci subsystem was fixed by properly clearing the vmci transport packet during initialization to avoid uninitialized data. This flaw could lead to serious impacts including confidentiality, integrity, and availability compromises. Multiple Linux kernel versions prior to 5.15.0-1092.99~20.04.1 and some older 3.x versions are affected. The issue is addressed in updated kernel releases. The vulnerability has a high severity score of 7.8 and no known exploits in the wild have been reported.
References
- ubuntu.com/security/CVE-2025-38403 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-38403 (opens in a new tab)
- git.kernel.org/linus/223e2288f4b8c262a864e2c03964ffac91744cd5 (opens in a new tab)
- git.kernel.org/stable/c/0a01021317375b8d1895152f544421ce49299eb1 (opens in a new tab)
- git.kernel.org/stable/c/19c2cc01ff9a8031398a802676ffb0f4692dd95d (opens in a new tab)
- git.kernel.org/stable/c/1c1bcb0e78230f533b4103e8cf271d17c3f469f0 (opens in a new tab)
- git.kernel.org/stable/c/223e2288f4b8c262a864e2c03964ffac91744cd5 (opens in a new tab)
- git.kernel.org/stable/c/2d44723a091bc853272e1a51a488a3d22b80be5e (opens in a new tab)
- git.kernel.org/stable/c/75705b44e0b9aaa74f4c163d93d388bcba9e386a (opens in a new tab)
- git.kernel.org/stable/c/94d0c326cb3ee6b0f8bd00e209550b93fcc5c839 (opens in a new tab)
- git.kernel.org/stable/c/e9a673153d578fd439919a24e99851b2f87ecbce (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7775-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7776-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7775-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7775-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-7774-5 (opens in a new tab)