CVE-2026-43209Public exploit

Service interruption via unchecked Minix superblock fields

Published May 6, 2026 · Updated May 6, 2026

Improper input validation in Linux Kernel Minix filesystem support allows local users to interrupt service via a crafted filesystem image. minix_check_superblock() accepts unsupported s_log_zone_size values and inconsistent inode, zone, and bitmap counts, which later drive an oversized shift in minix_statfs() and unsafe filesystem calculations. Reaching the flaw requires permission to mount or induce mounting of the malformed image; the demonstrated result is a kernel shift-out-of-bounds failure that can interrupt the host.

CVSS severity5.5
Medium
EPSS probability0.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Linux Kernel Minix filesystem support allows local users to interrupt service via a crafted filesystem image. minix_check_superblock() accepts unsupported s_log_zone_size values and inconsistent inode, zone, and bitmap counts, which later drive an oversized shift in minix_statfs() and unsafe filesystem calculations. Reaching the flaw requires permission to mount or induce mounting of the malformed image; the demonstrated result is a kernel shift-out-of-bounds failure that can interrupt the host.

The record

CVE
CVE-2026-43209
Published
May 6, 2026
Updated
May 6, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 6, 2026CVE publishedPublication date reported by the CVE source.
  2. May 6, 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=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <1efc128ee4adbc23e082715425ff895449d233bc
  2. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <2bb588cede1c1969e49c0a2822c8cb8b346b7682
  3. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <31fefc18096cdc5549cfa54964d90e0b3229aedc
  4. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <66c7c239c65341f99ae388d4d53dc9df2bcb9925
  5. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <8c97a6ddc95690a938ded44b4e3202f03f15078c
  6. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <a051ecf5c5b0387840dc210413ed3bc7fbdaa69c
  7. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <d791c544efd6b9c944b43cf7f502e5bcb02fb941
  8. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <f57ccd4657c7f082dc47e5b9e18a883bb5f9118f

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <1efc128ee4adbc23e082715425ff895449d233bc; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <2bb588cede1c1969e49c0a2822c8cb8b346b7682; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <31fefc18096cdc5549cfa54964d90e0b3229aedc; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <66c7c239c65341f99ae388d4d53dc9df2bcb9925; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <8c97a6ddc95690a938ded44b4e3202f03f15078c; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <a051ecf5c5b0387840dc210413ed3bc7fbdaa69c; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <d791c544efd6b9c944b43cf7f502e5bcb02fb941; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <f57ccd4657c7f082dc47e5b9e18a883bb5f9118f

Published CVSS scores

5.8SUSECVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N
5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.8SUSECVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/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 exploitPublished

Weakness, pattern, technique

T1499.004Application or System Exploitation

Public exploit references

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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