CVE-2025-68820

Kernel crash via unchecked inode lookup failure

Published Jan 13, 2026 · Updated Jan 13, 2026

Null pointer dereference in Linux Kernel 6.15 allows attackers to crash the kernel via ext4 extended-attribute cleanup. ext4_xattr_inode_dec_ref_all() continues after ext4_get_inode_loc() fails, leaving iloc.bh NULL before ext4_raw_inode() dereferences it. Triggering requires an inode-location lookup failure such as -EFSCORRUPTED during xattr reference cleanup, and the reported consequence is a kernel crash rather than data access.

CVSS severityUnavailable
Unscored
EPSS probability0.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Null pointer dereference in Linux Kernel 6.15 allows attackers to crash the kernel via ext4 extended-attribute cleanup. ext4_xattr_inode_dec_ref_all() continues after ext4_get_inode_loc() fails, leaving iloc.bh NULL before ext4_raw_inode() dereferences it. Triggering requires an inode-location lookup failure such as -EFSCORRUPTED during xattr reference cleanup, and the reported consequence is a kernel crash rather than data access.

The record

CVE
CVE-2025-68820
Published
Jan 13, 2026
Updated
Jan 13, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1499
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Jan 13, 2026CVE publishedPublication date reported by the CVE source.
  2. Jan 13, 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=362a90cecd36e8a5c415966d0b75b04a0270e4dd <b5d942922182e82724b7152cb998f540132885ec
  2. Affected versionversion=3bc6317033f365ce578eb6039445fb66162722fd
  3. Affected versionversion=6.15
  4. Affected versionversion=6aff941cb0f7d0c897c3698ad2e30672709135e3
  5. Affected versionversion=76c365fa7e2a8bb85f0190cdb4b8cdc99b2fdce3
  6. Affected versionversion=836e625b03a666cf93ff5be328c8cb30336db872
  7. Affected versionversion=c8e008b60492cf6fd31ef127aea6d02fd3d314cd <b97cb7d6a051aa6ebd57906df0e26e9e36c26d14
  8. Affected versionversion=c8e008b60492cf6fd31ef127aea6d02fd3d314cd <ce5f54c065a4a7cbb92787f4f140917112350142
  9. Affected versionversion=cf9291a3449b04688b81e32621e88de8f4314b54 <190ad0f22ba49f1101182b80e3af50ca2ddfe72f
  10. Affected versionversion=eb59cc31b6ea076021d14b04e7faab1636b87d0e <5b154e901fda2e98570b8f426a481f5740097dc2
  11. Affected versionversion=f737418b6de31c962c7192777ee4018906975383

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linux Kernelversion=362a90cecd36e8a5c415966d0b75b04a0270e4dd <b5d942922182e82724b7152cb998f540132885ec; version=3bc6317033f365ce578eb6039445fb66162722fd; version=6.15; version=6aff941cb0f7d0c897c3698ad2e30672709135e3; version=76c365fa7e2a8bb85f0190cdb4b8cdc99b2fdce3; version=836e625b03a666cf93ff5be328c8cb30336db872; version=c8e008b60492cf6fd31ef127aea6d02fd3d314cd <b97cb7d6a051aa6ebd57906df0e26e9e36c26d14; version=c8e008b60492cf6fd31ef127aea6d02fd3d314cd <ce5f54c065a4a7cbb92787f4f140917112350142; version=cf9291a3449b04688b81e32621e88de8f4314b54 <190ad0f22ba49f1101182b80e3af50ca2ddfe72f; version=eb59cc31b6ea076021d14b04e7faab1636b87d0e <5b154e901fda2e98570b8f426a481f5740097dc2; version=f737418b6de31c962c7192777ee4018906975383

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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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)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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