CVE-2025-22115

Local service interruption via btrfs refcount race

Published Apr 16, 2025 · Updated Aug 5, 2026

Race condition in the Linux kernel btrfs block-group code allows local users to interrupt service through filesystem writes. btrfs_create_pending_block_groups() removes and clears a new block group without holding unused_bg_lock while btrfs_mark_bg_unused() can concurrently move it, leaving a broken reference count and invalid new_bgs cleanup state. Write access to a mounted btrfs filesystem is sufficient; a triggered underflow produces a use-after-free warning and can disrupt the host.

CVSS severity7.8
High
EPSS probability0.15%
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

Race condition in the Linux kernel btrfs block-group code allows local users to interrupt service through filesystem writes. btrfs_create_pending_block_groups() removes and clears a new block group without holding unused_bg_lock while btrfs_mark_bg_unused() can concurrently move it, leaving a broken reference count and invalid new_bgs cleanup state. Write access to a mounted btrfs filesystem is sufficient; a triggered underflow produces a use-after-free warning and can disrupt the host.

The record

CVE
CVE-2025-22115
Published
Apr 16, 2025
Updated
Aug 5, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-362, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 16, 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=0657b20c5a76c938612f8409735a8830d257866e <2d8e5168d48a91e7a802d3003e72afb4304bebfa
  2. Affected versionversion=0657b20c5a76c938612f8409735a8830d257866e <9d383a6fc59271aaaf07a33b23b2eac5b9268b7a
  3. Affected versionversion=0657b20c5a76c938612f8409735a8830d257866e <ee56da95f8962b86fec4ef93f866e64c8d025a58
  4. Affected versionversion=6.1.47 <6.2
  5. Affected versionversion=6297644db23f77c02ae7961cc542d162629ae2c4
  6. Affected versionversion=6.4.12 <6.5
  7. Affected versionversion=6.5
  8. Affected versionversion=7569c4294ba6ff9f194635b14876198f8a687c4a

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=0657b20c5a76c938612f8409735a8830d257866e <2d8e5168d48a91e7a802d3003e72afb4304bebfa; version=0657b20c5a76c938612f8409735a8830d257866e <9d383a6fc59271aaaf07a33b23b2eac5b9268b7a; version=0657b20c5a76c938612f8409735a8830d257866e <ee56da95f8962b86fec4ef93f866e64c8d025a58; version=6.1.47 <6.2; version=6297644db23f77c02ae7961cc542d162629ae2c4; version=6.4.12 <6.5; version=6.5; version=7569c4294ba6ff9f194635b14876198f8a687c4a

Published CVSS scores

7.8kernel.orgCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
4.7NIST NVDCVSS:3.1/AV:L/AC:H/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.

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

CWE-362Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
T1499.004Application or System Exploitation

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