CVE-2025-38563: Linux kernel · perf/core: Prevent VMA split of buffer mappings
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 5.15.0-1097.104~20.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 10:12 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 34% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.15.0-1097.104~20.04.1, 5.15.0-1102.111~20.04.1, 5.15.0-1097.106~20.04.1 +32
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 19 Aug 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@6.17.0-1017.17?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinuxpkg:deb/ubuntu/linux@6.8.0-136.136?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-awspkg:deb/ubuntu/linux-aws@6.8.0-1060.63?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-aws-6.14pkg:deb/ubuntu/linux-aws-6.14@6.14.0-1017.17~24.04.1?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure@6.8.0-1062.69?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-azure-6.11pkg:deb/ubuntu/linux-azure-6.11@6.11.0-1018.18~24.04.1?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 that implements a kernel-level fix preventing VMA splits in perf mmap buffer mappings. Users should apply the official Linux kernel updates that include this fix. The vendor advisory confirms the availability of this update. No additional mitigation actions are specified or required beyond applying the patch.
Description
A vulnerability in the Linux kernel's perf subsystem related to mmap buffer mappings has been resolved. The issue involves improper handling of virtual memory area (VMA) splits that cause reference count leaks due to mismatched offset and size checks in perf mmap operations. This flaw could lead to resource management inconsistencies. The fix prevents VMA splits by implementing a callback that disallows splitting, ensuring mapping offsets and sizes remain consistent after initial mapping.
References
- ubuntu.com/security/CVE-2025-38563 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-38563 (opens in a new tab)
- git.kernel.org/linus/b024d7b56c77191cde544f838debb7f8451cd0d6 (opens in a new tab)
- git.kernel.org/stable/c/65311aad4c808bedad0c05d9bb8b06c47dae73eb (opens in a new tab)
- git.kernel.org/stable/c/6757a31a8e295ae4f01717a954afda173f25a121 (opens in a new tab)
- git.kernel.org/stable/c/7b84cb58d1f0aa07656802eae24689566e5f5b1b (opens in a new tab)
- git.kernel.org/stable/c/b024d7b56c77191cde544f838debb7f8451cd0d6 (opens in a new tab)
- git.kernel.org/stable/c/e529888b7e8092912dd8789bdfc76685ccd2ff5f (opens in a new tab)
- git.kernel.org/stable/c/ff668930871e0198c7f4e325058b8b7c286787bd (opens in a new tab)
- ubuntu.com/security/notices/USN-7879-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7879-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7880-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7879-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7909-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7879-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-7909-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7909-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7910-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7909-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-7910-2 (opens in a new tab)