CVE-2025-40105: Linux kernel · vfs: Don't leak disconnected dentries on umount
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 7.8 High · fixed in eadc49999fa994d6fbd70c332bd5d5051cc42261 : patch Linux kernel soon.
Data as of 10 Nov 2026, 14:47 UTC
Thin evidence
One scorer or none| CNA (Linux) | CVSS 3.1 | 7.8 |
|---|
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Total control over the software or total information disclosure
CISA SSVC assessment, 2026-10-15.
- Patch
- Available – fixed in eadc49999fa994d6fbd70c332bd5d5051cc42261, cebfbf40056a4d858b2a3ca59a69936d599bd209, b5abafd0aa8d7bcb935c8f91e4cfc2f2820759e4 +5
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 30 Oct 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 10 Nov 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
AI-suggested
A fix is available in the Linux kernel as indicated by multiple fixed commit versions. Users and administrators should update affected Linux kernel versions to the fixed releases to remediate this vulnerability. No additional mitigation is required beyond applying the official patch.
Description
CVE-2025-40105 is a vulnerability in the Linux kernel's virtual file system (vfs) related to memory leaks of disconnected dentries during unmount operations. The flaw occurs when disconnected dentries created under a disconnected parent are not properly marked as disconnected, causing them to remain in memory and potentially leading to "Busy inodes after unmount" errors. This issue was fixed by ensuring all dentries created under a disconnected parent are also marked as disconnected.
References
- git.kernel.org/stable/c/b5abafd0aa8d7bcb935c8f91e4cfc2f2820759e4 (opens in a new tab)
- git.kernel.org/stable/c/20863bb7fbb016379f8227122edfabc5c799bc79 (opens in a new tab)
- git.kernel.org/stable/c/8004d4b8cbf1bd68a23c160d57287e177c82cc69 (opens in a new tab)
- git.kernel.org/stable/c/7e0c8aaf4e28918abded547a5147c7d52c4af7d2 (opens in a new tab)
- git.kernel.org/stable/c/cebfbf40056a4d858b2a3ca59a69936d599bd209 (opens in a new tab)
- git.kernel.org/stable/c/620f3b0ede9c5cb4976cd0457d0b04ad551e5d6b (opens in a new tab)
- git.kernel.org/stable/c/eadc49999fa994d6fbd70c332bd5d5051cc42261 (opens in a new tab)
- git.kernel.org/stable/c/56094ad3eaa21e6621396cc33811d8f72847a834 (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-019113.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-457936.html (opens in a new tab)