CVE-2025-21699

Local privilege escalation via stale GFS2 page state

Published Feb 12, 2025 · Updated Aug 5, 2026

Type confusion in the Linux GFS2 file path allows local users to escalate privileges by changing an inode's journaling mode. When file.c flips GFS2_DIF_JDATA, it retains cached pages whose private data uses the former buffer-head or iomap_folio_state layout, so later operations interpret one structure as the other. A local user with write access to a GFS2 file can trigger out-of-bounds access, use-after-free, kernel memory corruption, and a system crash.

CVSS severity7.8
High
EPSS probability0.25%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Type confusion in the Linux GFS2 file path allows local users to escalate privileges by changing an inode's journaling mode. When file.c flips GFS2_DIF_JDATA, it retains cached pages whose private data uses the former buffer-head or iomap_folio_state layout, so later operations interpret one structure as the other. A local user with write access to a GFS2 file can trigger out-of-bounds access, use-after-free, kernel memory corruption, and a system crash.

The record

CVE
CVE-2025-21699
Published
Feb 12, 2025
Updated
Aug 5, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 12, 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

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=2164f9b9186962ffb7c687e18ec6f5255525f09d <2a40a140e11fec699e128170ccaa98b6b82cb503
  2. Affected versionversion=2164f9b9186962ffb7c687e18ec6f5255525f09d <4516febe325342555bb09ca5b396fb816d655821
  3. Affected versionversion=2164f9b9186962ffb7c687e18ec6f5255525f09d <4dd57d1f0e9844311c635a7fb39abce4f2ac5a61
  4. Affected versionversion=2164f9b9186962ffb7c687e18ec6f5255525f09d <4e3ded34f3f3c9d7ed2aac7be8cf51153646574a
  5. Affected versionversion=2164f9b9186962ffb7c687e18ec6f5255525f09d <5bb1fd0855bb0abc7d97e44758d6ffed7882d2d0
  6. Affected versionversion=2164f9b9186962ffb7c687e18ec6f5255525f09d <7c9d9223802fbed4dee1ae301661bf346964c9d2
  7. Affected versionversion=2164f9b9186962ffb7c687e18ec6f5255525f09d <8c41abc11aa8438c9ed2d973f97e66674c0355df
  8. Affected versionversion=5.10

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=2164f9b9186962ffb7c687e18ec6f5255525f09d <2a40a140e11fec699e128170ccaa98b6b82cb503; version=2164f9b9186962ffb7c687e18ec6f5255525f09d <4516febe325342555bb09ca5b396fb816d655821; version=2164f9b9186962ffb7c687e18ec6f5255525f09d <4dd57d1f0e9844311c635a7fb39abce4f2ac5a61; version=2164f9b9186962ffb7c687e18ec6f5255525f09d <4e3ded34f3f3c9d7ed2aac7be8cf51153646574a; version=2164f9b9186962ffb7c687e18ec6f5255525f09d <5bb1fd0855bb0abc7d97e44758d6ffed7882d2d0; version=2164f9b9186962ffb7c687e18ec6f5255525f09d <7c9d9223802fbed4dee1ae301661bf346964c9d2; version=2164f9b9186962ffb7c687e18ec6f5255525f09d <8c41abc11aa8438c9ed2d973f97e66674c0355df; version=5.10

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
6.0Amazon LinuxCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H
7.8Linux kernel CNACVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 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

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo