CVE-2025-38097: Linux kernel · espintcp: remove encap socket caching to avoid reference leak
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 6.8.0-1046.49~22.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 16:39 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 9% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 6.8.0-1046.49~22.04.1, 6.8.0-1051.57~22.04.1, 6.8.0-1046.53~22.04.1 +33
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 3 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.
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 to affected Linux kernel versions to remove the encapsulation socket caching and prevent reference leaks. The Ubuntu security advisory USN-7769-1 provides updated kernel packages that address this vulnerability. Applying these official updates is the recommended remediation.
Description
A vulnerability in the Linux kernel's espintcp subsystem involving the caching of encapsulation sockets could lead to reference leaks that prevent proper deletion of network namespaces. This issue arises because the current caching scheme holds references that may block netns deletion, causing resource retention. The vulnerability has been addressed by removing the encap socket caching, which may cause a minor performance regression. Multiple Linux kernel versions are affected, and a patch is available.
References
- ubuntu.com/security/CVE-2025-38097 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-38097 (opens in a new tab)
- git.kernel.org/linus/028363685bd0b7a19b4a820f82dd905b1dc83999 (opens in a new tab)
- git.kernel.org/stable/c/028363685bd0b7a19b4a820f82dd905b1dc83999 (opens in a new tab)
- git.kernel.org/stable/c/74fd327767fb784c5875cf7c4ba1217f26020943 (opens in a new tab)
- git.kernel.org/stable/c/9cbca30102028f9ad3d2098f935c4368f581fd07 (opens in a new tab)
- git.kernel.org/stable/c/b58a295d10065960bcb9d60cb8ca6ead9837cd27 (opens in a new tab)
- git.kernel.org/stable/c/e4cde54b46a87231c77256a633be1bef62687d69 (opens in a new tab)
- ubuntu.com/security/notices/USN-7769-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7770-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7771-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7769-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7769-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7789-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7789-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8028-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8028-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8031-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8028-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8028-4 (opens in a new tab)