CVE-2022-49343

Service interruption via cyclic ext4 directory h-tree

Published Feb 26, 2025 · Updated Aug 5, 2026

Memory-safety flaw in affected Linux ext4 kernels allows local users to interrupt service through a maliciously corrupted filesystem. During a directory h-tree node split, ext4 follows cyclic block references, reuses nodes already validated, and then accesses unallocated memory. Exploitation requires the crafted ext4 filesystem to be mounted and a directory operation to trigger a node split; the documented consequence is limited to kernel service interruption.

CVSS severity5.5
Medium
EPSS probability0.29%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Memory-safety flaw in affected Linux ext4 kernels allows local users to interrupt service through a maliciously corrupted filesystem. During a directory h-tree node split, ext4 follows cyclic block references, reuses nodes already validated, and then accesses unallocated memory. Exploitation requires the crafted ext4 filesystem to be mounted and a directory operation to trigger a node split; the documented consequence is limited to kernel service interruption.

The record

CVE
CVE-2022-49343
Published
Feb 26, 2025
Updated
Aug 5, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 26, 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=2.6.19
  2. Affected versionversion=ac27a0ec112a089f1a5102bc8dffc79c8c815571 <24b8206fec1db21d7e82f21f0b2ff5e5672cf5b3
  3. Affected versionversion=ac27a0ec112a089f1a5102bc8dffc79c8c815571 <3a3ce941645407cd0b0b7f01ad9e2ea3770f46cc
  4. Affected versionversion=ac27a0ec112a089f1a5102bc8dffc79c8c815571 <3ba733f879c2a88910744647e41edeefbc0d92b2
  5. Affected versionversion=ac27a0ec112a089f1a5102bc8dffc79c8c815571 <6084240bfc44bf265ab6ae7d96980469b05be0f1
  6. Affected versionversion=ac27a0ec112a089f1a5102bc8dffc79c8c815571 <b3ad9ff6f06c1dc6abf7437691c88ca3d6da3ac0
  7. Affected versionversion=ac27a0ec112a089f1a5102bc8dffc79c8c815571 <d5a16a6df2c16eaf4de04948553ef0089dee463f
  8. Affected versionversion=ac27a0ec112a089f1a5102bc8dffc79c8c815571 <e157c8f87e8fac112d6c955e69a60cdb9bc80a60
  9. Affected versionversion=ac27a0ec112a089f1a5102bc8dffc79c8c815571 <ff4cafa51762da3824881a9000ca421d4b78b138

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=2.6.19; version=ac27a0ec112a089f1a5102bc8dffc79c8c815571 <24b8206fec1db21d7e82f21f0b2ff5e5672cf5b3; version=ac27a0ec112a089f1a5102bc8dffc79c8c815571 <3a3ce941645407cd0b0b7f01ad9e2ea3770f46cc; version=ac27a0ec112a089f1a5102bc8dffc79c8c815571 <3ba733f879c2a88910744647e41edeefbc0d92b2; version=ac27a0ec112a089f1a5102bc8dffc79c8c815571 <6084240bfc44bf265ab6ae7d96980469b05be0f1; version=ac27a0ec112a089f1a5102bc8dffc79c8c815571 <b3ad9ff6f06c1dc6abf7437691c88ca3d6da3ac0; version=ac27a0ec112a089f1a5102bc8dffc79c8c815571 <d5a16a6df2c16eaf4de04948553ef0089dee463f; version=ac27a0ec112a089f1a5102bc8dffc79c8c815571 <e157c8f87e8fac112d6c955e69a60cdb9bc80a60; version=ac27a0ec112a089f1a5102bc8dffc79c8c815571 <ff4cafa51762da3824881a9000ca421d4b78b138

Published CVSS scores

5.5UbuntuCVSS: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

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

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Your stack

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