Linux Kernel up to 6.12.15/6.13.3/6.14-rc2 am65_cpsw_build_skb allocation of resources

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.12.15/6.13.3/6.14-rc2. It has been rated as critical. The affected element is the function am65_cpsw_build_skb. This manipulation causes allocation of resources. This vulnerability is tracked as CVE-2025-21788. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.12.15/6.13.3/6.14-rc2 and classified as critical. Affected by this vulnerability is the function am65_cpsw_build_skb. The manipulation with an unknown input leads to a allocation of resources vulnerability. The CWE definition for the vulnerability is CWE-770. The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor. As an impact it is known to affect availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: net: ethernet: ti: am65-cpsw: fix memleak in certain XDP cases If the XDP program doesn't result in XDP_PASS then we leak the memory allocated by am65_cpsw_build_skb(). It is pointless to allocate SKB memory before running the XDP program as we would be wasting CPU cycles for cases other than XDP_PASS. Move the SKB allocation after evaluating the XDP program result. This fixes the memleak. A performance boost is seen for XDP_DROP test. XDP_DROP test: Before: 460256 rx/s 0 err/s After: 784130 rx/s 0 err/s

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2025-21788 since 12/29/2024. Technical details of the vulnerability are known, but there is no available exploit.

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 6.12.16, 6.13.4 or 6.14-rc3 eliminates this vulnerability. Applying the patch 1bba1d042107167164a0ae3a843fdf650ab005d7/dc11f049612b9d926aca2e55f8dc9d82850d0da3/5db843258de1e4e6b1ef1cbd1797923c9e3de548 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-2025-0453). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Google Container-Optimized OS
• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• Siemens SIMATIC S7
• RESF Rocky Linux
• Dell NetWorker
• Dell Avamar
• Red Hat OpenShift
• IBM QRadar SIEM
• SolarWinds Security Event Manager
• Dell PowerProtect Data Domain
• Open Source Linux Kernel
• IBM DataPower Gateway
• Dell Secure Connect Gateway
• Dell PowerScale OneFS
• Dell ECS

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.12.0
• 6.12.1
• 6.12.2
• 6.12.3
• 6.12.4
• 6.12.5
• 6.12.6
• 6.12.7
• 6.12.8
• 6.12.9
• 6.12.10
• 6.12.11
• 6.12.12
• 6.12.13
• 6.12.14
• 6.12.15
• 6.13.0
• 6.13.1
• 6.13.2
• 6.13.3
• 6.14-rc1
• 6.14-rc2

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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