Linux Kernel up to 6.1.161/6.6.122/6.12.68/6.18.8 efivarfs efivar_entry_get uninitialized pointer

CVSS Meta Temp Score
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CTI Interest Score
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6.5$0-$5k0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.1.161/6.6.122/6.12.68/6.18.8 and classified as critical. Affected by this issue is the function efivar_entry_get of the component efivarfs. Such manipulation leads to uninitialized pointer. This vulnerability is listed as CVE-2026-23156. There is no available exploit. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.1.161/6.6.122/6.12.68/6.18.8 and classified as critical. Affected by this issue is the function efivar_entry_get of the component efivarfs. The manipulation with an unknown input leads to a uninitialized pointer vulnerability. Using CWE to declare the problem leads to CWE-824. The product accesses or uses a pointer that has not been initialized. The impact remains unknown. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: efivarfs: fix error propagation in efivar_entry_get() efivar_entry_get() always returns success even if the underlying __efivar_entry_get() fails, masking errors. This may result in uninitialized heap memory being copied to userspace in the efivarfs_file_read() path. Fix it by returning the error from __efivar_entry_get().

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2026-23156 since 01/13/2026. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 05/05/2026).

The vulnerability scanner Nessus provides a plugin with the ID 299150 (Linux Distros Unpatched Vulnerability : CVE-2026-23156), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.162, 6.6.123, 6.12.69 or 6.18.9 eliminates this vulnerability. Applying the patch 3960f1754664661a970dc9ebbab44ff93a0b4c42/510a16f1c5c1690b33504052bc13fbc2772c23f8/89b8ca709eeeabcc11ebba64806677873a2787a8/e4e15a0a4403c96d9898d8398f0640421df9cb16/4b22ec1685ce1fc0d862dcda3225d852fb107995 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (299150) and CERT Bund (WID-SEC-2026-0421). Once again VulDB remains the best source for vulnerability data.

Affected

  • Google Container-Optimized OS
  • Debian Linux
  • Google Cloud Platform
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • RESF Rocky Linux
  • Open Source Linux Kernel
  • IBM QRadar SIEM

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.6
VulDB Meta Temp Score: 6.5

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Uninitialized pointer
CWE: CWE-824 / CWE-908
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 299150
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-23156

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.1.162/6.6.123/6.12.69/6.18.9
Patch: 3960f1754664661a970dc9ebbab44ff93a0b4c42/510a16f1c5c1690b33504052bc13fbc2772c23f8/89b8ca709eeeabcc11ebba64806677873a2787a8/e4e15a0a4403c96d9898d8398f0640421df9cb16/4b22ec1685ce1fc0d862dcda3225d852fb107995

Timelineinfo

01/13/2026 CVE reserved
02/14/2026 +32 days Advisory disclosed
02/14/2026 +0 days VulDB entry created
05/05/2026 +80 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-23156 (🔒)
GCVE (CVE): GCVE-0-2026-23156
GCVE (VulDB): GCVE-100-346028
CERT Bund: WID-SEC-2026-0421 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 02/14/2026 17:57
Updated: 05/05/2026 16:52
Changes: 02/14/2026 17:57 (59), 02/17/2026 02:07 (2), 02/19/2026 10:55 (1), 03/09/2026 11:50 (7), 03/19/2026 04:56 (11), 04/13/2026 01:14 (1), 05/05/2026 16:52 (1)
Complete: 🔍
Cache ID: 216::103

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