CVE-2025-38321

Local kernel corruption via CIFS unmount allocation failure

Published Jul 10, 2025 · Updated Aug 5, 2026

Memory corruption in the Linux kernel CIFS client allows local users to corrupt kernel memory during a low-memory SMB unmount. close_all_cached_dirs() can fail to allocate a temporary dentry list, leaving references that outlive superblock destruction and causing later dput() operations to read and write freed kernel memory. A low-privileged local account can reach the path through user-mountable or automounted SMB shares, resulting in kernel read/write primitives or a panic.

CVSS severity5.5
Medium
EPSS probability0.17%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Memory corruption in the Linux kernel CIFS client allows local users to corrupt kernel memory during a low-memory SMB unmount. close_all_cached_dirs() can fail to allocate a temporary dentry list, leaving references that outlive superblock destruction and causing later dput() operations to read and write freed kernel memory. A low-privileged local account can reach the path through user-mountable or automounted SMB shares, resulting in kernel read/write primitives or a panic.

The record

CVE
CVE-2025-38321
Published
Jul 10, 2025
Updated
Aug 5, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 10, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=3fa640d035e5ae526769615c35cb9ed4be6e3662 <4479db143390bdcadc1561292aab579cdfa9f6c6
  2. Affected versionversion=3fa640d035e5ae526769615c35cb9ed4be6e3662 <a2182743a8b4969481f64aec4908ff162e8a206c
  3. Affected versionversion=548812afd96982a76a93ba76c0582ea670c40d9e <43f26094d6702e494e800532c3f1606e7a68eb30
  4. Affected versionversion=6.11.11 <6.12
  5. Affected versionversion=6.12.2 <6.12.35
  6. Affected versionversion=6.13
  7. Affected versionversion=6.6.64 <6.6.95
  8. Affected versionversion=73934e535cffbda1490fa97d82690a0f9aa73e94 <b8ced2b9a23a1a2c1e0ed8d0d02512e51bdf38da
  9. Affected versionversion=ff4528bbc82d0d90073751f7b49e7b9e9c7e5638

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=3fa640d035e5ae526769615c35cb9ed4be6e3662 <4479db143390bdcadc1561292aab579cdfa9f6c6; version=3fa640d035e5ae526769615c35cb9ed4be6e3662 <a2182743a8b4969481f64aec4908ff162e8a206c; version=548812afd96982a76a93ba76c0582ea670c40d9e <43f26094d6702e494e800532c3f1606e7a68eb30; version=6.11.11 <6.12; version=6.12.2 <6.12.35; version=6.13; version=6.6.64 <6.6.95; version=73934e535cffbda1490fa97d82690a0f9aa73e94 <b8ced2b9a23a1a2c1e0ed8d0d02512e51bdf38da; version=ff4528bbc82d0d90073751f7b49e7b9e9c7e5638

Published CVSS scores

7.8LinuxCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
5.5NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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