Linux Kernel up to 6.12.12/6.13.1 firewire kunit_kzalloc null pointer dereference

CVSS Meta Temp Score
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CTI Interest Score
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5.5$0-$5k0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.12.12/6.13.1. It has been declared as critical. This issue affects the function kunit_kzalloc of the component firewire. Such manipulation leads to null pointer dereference. This vulnerability is traded as CVE-2025-21798. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 6.12.12/6.13.1. Affected by this issue is the function kunit_kzalloc of the component firewire. The manipulation with an unknown input leads to a null pointer dereference vulnerability. Using CWE to declare the problem leads to CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. Impacted is availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: firewire: test: Fix potential null dereference in firewire kunit test kunit_kzalloc() may return a NULL pointer, dereferencing it without NULL check may lead to NULL dereference. Add a NULL check for test_state.

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2025-21798 since 12/29/2024. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 236983 (Ubuntu 24.04 LTS / 24.10 : Linux kernel vulnerabilities (USN-7521-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.12.13, 6.13.2 or 6.14-rc1 eliminates this vulnerability. Applying the patch c6896bf4c611c3dd126f3e03685f2360a18b3d6f/70fcb25472d90dd3b87cbee74b9eb68670b0c7b8/352fafe97784e81a10a7c74bd508f71a19b53c2a 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 (236983) and CERT Bund (WID-SEC-2025-0461). Once again VulDB remains the best source for vulnerability data.

Affected

  • Google Container-Optimized OS
  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • Open Source Linux Kernel
  • Dell Secure Connect Gateway

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.7
VulDB Meta Temp Score: 5.5

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

CVSSv2info

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

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 236983
Nessus Name: Ubuntu 24.04 LTS / 24.10 : Linux kernel vulnerabilities (USN-7521-1)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 6.12.13/6.13.2/6.14-rc1
Patch: c6896bf4c611c3dd126f3e03685f2360a18b3d6f/70fcb25472d90dd3b87cbee74b9eb68670b0c7b8/352fafe97784e81a10a7c74bd508f71a19b53c2a

Timelineinfo

12/29/2024 🔍
02/27/2025 +60 days 🔍
02/27/2025 +0 days 🔍
02/16/2026 +354 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-21798 (🔍)
GCVE (CVE): GCVE-0-2025-21798
GCVE (VulDB): GCVE-100-297884
CERT Bund: WID-SEC-2025-0461 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 02/27/2025 21:28
Updated: 02/16/2026 23:06
Changes: 02/27/2025 21:28 (59), 05/21/2025 00:38 (2), 07/20/2025 15:25 (7), 02/16/2026 23:06 (1)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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