CVE-2026-45915

Conditional kernel panic via FAT link-count underflow

Published May 27, 2026 · Updated May 27, 2026

Denial of service in affected Linux Kernel releases allows local users to trigger a kernel warning through a corrupted FAT image. The vfat_rmdir() and msdos_rmdir() paths call drop_nlink() when a malformed parent inode reports i_nlink as 2, reducing it to 0 and firing WARN_ON. Reaching the flaw requires directory removal on a mounted corrupted FAT filesystem; service interruption occurs only when warning handling is configured to panic.

CVSS severity5.5
Medium
EPSS probability0.16%
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 affected Linux Kernel releases allows local users to trigger a kernel warning through a corrupted FAT image. The vfat_rmdir() and msdos_rmdir() paths call drop_nlink() when a malformed parent inode reports i_nlink as 2, reducing it to 0 and firing WARN_ON. Reaching the flaw requires directory removal on a mounted corrupted FAT filesystem; service interruption occurs only when warning handling is configured to panic.

The record

CVE
CVE-2026-45915
Published
May 27, 2026
Updated
May 27, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
Unavailable
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 27, 2026CVE publishedPublication date reported by the CVE source.
  2. May 27, 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=2.6.19
  2. Affected versionversion=9a53c3a783c2fa9b969628e65695c11c3e51e673 <17866f8a0822d414cb02e621cf003a7d04396ef8
  3. Affected versionversion=9a53c3a783c2fa9b969628e65695c11c3e51e673 <7fe0de287e931e07cb96ecf1f449b2ebdb0e1115
  4. Affected versionversion=9a53c3a783c2fa9b969628e65695c11c3e51e673 <8cafcb881364af5ef3a8b9fed4db254054033d8a
  5. Affected versionversion=9a53c3a783c2fa9b969628e65695c11c3e51e673 <955c5d670b5ae07c78f4345e23a895638db96ce1
  6. Affected versionversion=9a53c3a783c2fa9b969628e65695c11c3e51e673 <9894c79fd9466612d0514be157b5c30cd93aa645
  7. Affected versionversion=9a53c3a783c2fa9b969628e65695c11c3e51e673 <cd569b87378b9c33ae13c23d6bb9d205d66f7c4b
  8. Affected versionversion=9a53c3a783c2fa9b969628e65695c11c3e51e673 <d0bb592fa9def2bace90ac8926c0a1d6fa8c1aa0
  9. Affected versionversion=9a53c3a783c2fa9b969628e65695c11c3e51e673 <d3b7ffa90f613938128432c7b2f35b7aa4bdd86b

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=2.6.19; version=9a53c3a783c2fa9b969628e65695c11c3e51e673 <17866f8a0822d414cb02e621cf003a7d04396ef8; version=9a53c3a783c2fa9b969628e65695c11c3e51e673 <7fe0de287e931e07cb96ecf1f449b2ebdb0e1115; version=9a53c3a783c2fa9b969628e65695c11c3e51e673 <8cafcb881364af5ef3a8b9fed4db254054033d8a; version=9a53c3a783c2fa9b969628e65695c11c3e51e673 <955c5d670b5ae07c78f4345e23a895638db96ce1; version=9a53c3a783c2fa9b969628e65695c11c3e51e673 <9894c79fd9466612d0514be157b5c30cd93aa645; version=9a53c3a783c2fa9b969628e65695c11c3e51e673 <cd569b87378b9c33ae13c23d6bb9d205d66f7c4b; version=9a53c3a783c2fa9b969628e65695c11c3e51e673 <d0bb592fa9def2bace90ac8926c0a1d6fa8c1aa0; version=9a53c3a783c2fa9b969628e65695c11c3e51e673 <d3b7ffa90f613938128432c7b2f35b7aa4bdd86b

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

No sourced classifications are available.

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