CVE-2025-39884: Linux kernel · btrfs: fix subvolume deletion lockup caused by inodes xarray race
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 4.7 Medium.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 1% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 23 Sep 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
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@6.14.0-1018.18~24.04.1?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 fix is available that corrects the race condition by verifying the inode before deleting the xarray entry. Users should apply the official Linux kernel updates that include this patch. Since this is a kernel-level issue, updating to a fixed kernel version is the recommended remediation.
Description
A race condition in the Linux kernel's Btrfs filesystem can cause a subvolume deletion lockup. This occurs due to a timing window where inode eviction and caching operations conflict, potentially leading to an infinite loop during subvolume deletion and resulting in system soft lockups.
References
- ubuntu.com/security/CVE-2025-39884 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-39884 (opens in a new tab)
- git.kernel.org/linus/f6a6c280059c4ddc23e12e3de1b01098e240036f (opens in a new tab)
- git.kernel.org/stable/c/9ba898c9fcbe6ebb88bcd4df8aab0f90090d202e (opens in a new tab)
- git.kernel.org/stable/c/f1498abaf74f8d7b1e7001f16ed77818d8ae6a59 (opens in a new tab)
- git.kernel.org/stable/c/f6a6c280059c4ddc23e12e3de1b01098e240036f (opens in a new tab)