CVE-2022-48664

Unmount hang via delayed-iput reclaim deadlock

Published Apr 28, 2024 · Updated May 23, 2026

Denial of service in the Linux kernel's Btrfs subsystem allows local users to hang filesystem unmount under metadata pressure. In close_ctree, the cleaner thread can park while delayed iputs remain pending, leaving async reclaim blocked as cancel_work_sync waits indefinitely. A local user must exercise and unmount a Btrfs volume under sustained metadata pressure; success blocks unmount and interrupts storage service.

CVSS severity5.5
Medium
EPSS probability0.24%
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

Denial of service in the Linux kernel's Btrfs subsystem allows local users to hang filesystem unmount under metadata pressure. In close_ctree, the cleaner thread can park while delayed iputs remain pending, leaving async reclaim blocked as cancel_work_sync waits indefinitely. A local user must exercise and unmount a Btrfs volume under sustained metadata pressure; success blocks unmount and interrupts storage service.

The record

CVE
CVE-2022-48664
Published
Apr 28, 2024
Updated
May 23, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 28, 2024CVE publishedPublication date reported by the CVE source.
  2. May 23, 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=1ec2bf44c3770b9c3d510b1e78d50cd7fd19e8c5
  2. Affected versionversion=4.14.120 <4.15
  3. Affected versionversion=4.19.12 <4.20
  4. Affected versionversion=4.20
  5. Affected versionversion=b4c7c826709b7d882ec9b264d5032e887e6bd720
  6. Affected versionversion=d6fd0ae25c6495674dc5a41a8d16bc8e0073276d <6ac5b52e3f352f9cb270c89e6e1d4dadb564ddb8
  7. Affected versionversion=d6fd0ae25c6495674dc5a41a8d16bc8e0073276d <a362bb864b8db4861977d00bd2c3222503ccc34b
  8. Affected versionversion=d6fd0ae25c6495674dc5a41a8d16bc8e0073276d <c338bea1fec5504290dc0acf026c9e7dba25004b
  9. Affected versionversion=d6fd0ae25c6495674dc5a41a8d16bc8e0073276d <d8a76a2e514fbbb315a6dfff2d342de2de833994

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=1ec2bf44c3770b9c3d510b1e78d50cd7fd19e8c5; version=4.14.120 <4.15; version=4.19.12 <4.20; version=4.20; version=b4c7c826709b7d882ec9b264d5032e887e6bd720; version=d6fd0ae25c6495674dc5a41a8d16bc8e0073276d <6ac5b52e3f352f9cb270c89e6e1d4dadb564ddb8; version=d6fd0ae25c6495674dc5a41a8d16bc8e0073276d <a362bb864b8db4861977d00bd2c3222503ccc34b; version=d6fd0ae25c6495674dc5a41a8d16bc8e0073276d <c338bea1fec5504290dc0acf026c9e7dba25004b; version=d6fd0ae25c6495674dc5a41a8d16bc8e0073276d <d8a76a2e514fbbb315a6dfff2d342de2de833994

Published CVSS scores

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.

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

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

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