CVE-2026-43349

Local service interruption via uninitialized F2FS folio

Published May 8, 2026 · Updated May 8, 2026

Use of uninitialized data in Linux Kernel F2FS allows local users to interrupt service during filesystem mounting. After a device read fails, f2fs_finish_read_bio passes an uninitialized folio to f2fs_sanity_check_node_footer instead of rejecting the failed I/O. Reaching the flaw requires local access and an F2FS read failure; the documented consequence is loss of availability, not data disclosure or modification.

CVSS severity5.5
Medium
EPSS probability0.11%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use of uninitialized data in Linux Kernel F2FS allows local users to interrupt service during filesystem mounting. After a device read fails, f2fs_finish_read_bio passes an uninitialized folio to f2fs_sanity_check_node_footer instead of rejecting the failed I/O. Reaching the flaw requires local access and an F2FS read failure; the documented consequence is loss of availability, not data disclosure or modification.

The record

CVE
CVE-2026-43349
Published
May 8, 2026
Updated
May 8, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-908, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 8, 2026CVE publishedPublication date reported by the CVE source.
  2. May 8, 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=50ac3ecd8e05b6bcc350c71a4307d40c030ec7e4 <7b9161a605e91d0987e2596a245dc1f21621b23f
  2. Affected versionversion=50ac3ecd8e05b6bcc350c71a4307d40c030ec7e4 <a10b89343d41ceee1af0ec38d3a74e526c77fa09
  3. Affected versionversion=7.0
  4. Affected versionversion=855c54f1803e3ebc613677b4f389c7f92656a1fc <59970b2586fef4b13e96527b9d232bed30b640cd
  5. Affected versionversion=c386753db52b3a80afa6612bfdcb925aa5ca260f

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=50ac3ecd8e05b6bcc350c71a4307d40c030ec7e4 <7b9161a605e91d0987e2596a245dc1f21621b23f; version=50ac3ecd8e05b6bcc350c71a4307d40c030ec7e4 <a10b89343d41ceee1af0ec38d3a74e526c77fa09; version=7.0; version=855c54f1803e3ebc613677b4f389c7f92656a1fc <59970b2586fef4b13e96527b9d232bed30b640cd; version=c386753db52b3a80afa6612bfdcb925aa5ca260f

Published CVSS scores

5.5NIST NVDCVSS: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 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-908Use of Uninitialized Resource
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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