Linux Kernel up to 6.12.39/6.15.7 efivarfs_fs_info initialization

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CTI Interest Score
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5.5$0-$5k0.00

Summaryinfo

A vulnerability classified as critical was found in Linux Kernel up to 6.12.39/6.15.7. Affected by this issue is the function efivarfs_fs_info. The manipulation results in initialization. This vulnerability is identified as CVE-2025-38549. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 6.12.39/6.15.7. Affected is the function efivarfs_fs_info. The manipulation with an unknown input leads to a initialization vulnerability. CWE is classifying the issue as CWE-665. The product does not initialize or incorrectly initializes a resource, which might leave the resource in an unexpected state when it is accessed or used. This is going to have an impact on availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: efivarfs: Fix memory leak of efivarfs_fs_info in fs_context error paths When processing mount options, efivarfs allocates efivarfs_fs_info (sfi) early in fs_context initialization. However, sfi is associated with the superblock and typically freed when the superblock is destroyed. If the fs_context is released (final put) before fill_super is called—such as on error paths or during reconfiguration—the sfi structure would leak, as ownership never transfers to the superblock. Implement the .free callback in efivarfs_context_ops to ensure any allocated sfi is properly freed if the fs_context is torn down before fill_super, preventing this memory leak.

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2025-38549 since 04/16/2025. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 276629 (Ubuntu 24.04 LTS / 25.04 : Linux kernel vulnerabilities (USN-7879-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.12.40 or 6.15.8 eliminates this vulnerability. Applying the patch 816d36973467d1c9c08a48bdffe4675e219a2e84/e9fabe7036bb8be6071f39dc38605508f5f57b20/64e135f1eaba0bbb0cdee859af3328c68d5b9789 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 (276629), EUVD (EUVD-2025-25099) and CERT Bund (WID-SEC-2025-1858). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • RESF Rocky Linux
  • Dell Avamar
  • Open Source Linux Kernel
  • Dell NetWorker
  • Dell Secure Connect Gateway
  • IBM QRadar SIEM
  • IBM Security Verify Access

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.6
VulDB Meta Temp Score: 5.5

VulDB Base Score: 5.7
VulDB Temp Score: 5.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Initialization
CWE: CWE-665
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: 276629
Nessus Name: Ubuntu 24.04 LTS / 25.04 : Linux kernel vulnerabilities (USN-7879-1)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.12.40/6.15.8
Patch: 816d36973467d1c9c08a48bdffe4675e219a2e84/e9fabe7036bb8be6071f39dc38605508f5f57b20/64e135f1eaba0bbb0cdee859af3328c68d5b9789

Timelineinfo

04/16/2025 CVE reserved
08/16/2025 +122 days Advisory disclosed
08/16/2025 +0 days VulDB entry created
01/30/2026 +167 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-38549 (🔒)
GCVE (CVE): GCVE-0-2025-38549
GCVE (VulDB): GCVE-100-320376
EUVD: 🔒
CERT Bund: WID-SEC-2025-1858 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 08/16/2025 14:36
Updated: 01/30/2026 20:38
Changes: 08/16/2025 14:36 (58), 08/16/2025 15:45 (1), 09/28/2025 10:39 (7), 10/03/2025 17:31 (1), 10/12/2025 21:00 (1), 11/01/2025 22:02 (1), 11/19/2025 01:37 (11), 11/25/2025 04:02 (2), 01/30/2026 20:38 (1)
Complete: 🔍
Cache ID: 216::103

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