Linux Kernel up to 6.1.154/6.6.108/6.12.49/6.16.9 octeontx2-pf otx2_tc_add_flow use after free

Summaryinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 6.1.154/6.6.108/6.12.49/6.16.9. This issue affects the function otx2_tc_add_flow of the component octeontx2-pf. This manipulation causes use after free. This vulnerability is handled as CVE-2025-39978. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.1.154/6.6.108/6.12.49/6.16.9. It has been declared as critical. Affected by this vulnerability is the function otx2_tc_add_flow of the component octeontx2-pf. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: octeontx2-pf: Fix potential use after free in otx2_tc_add_flow() This code calls kfree_rcu(new_node, rcu) and then dereferences "new_node" and then dereferences it on the next line. Two lines later, we take a mutex so I don't think this is an RCU safe region. Re-order it to do the dereferences before queuing up the free.

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2025-39978 since 04/16/2025. The exploitation appears to be easy. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 02/08/2026).

The vulnerability scanner Nessus provides a plugin with the ID 271564 (Linux Distros Unpatched Vulnerability : CVE-2025-39978), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.155, 6.6.109, 6.12.50 or 6.16.10 eliminates this vulnerability. Applying the patch 5723120423a753a220b8b2954b273838b9d7e74a/df2c071061ed52d2225d97b212d27ecedf456b8a/c41b2941a024d4ec7c768e16ffb10a74b188fced/a8a63f27c3a8a3714210d32b12fd0f16d0337414/d9c70e93ec5988ab07ad2a92d9f9d12867f02c56 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 (271564) and CERT Bund (WID-SEC-2025-2298). 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
• SUSE openSUSE
• RESF Rocky Linux
• Open Source Linux Kernel
• IBM QRadar SIEM
• Dell NetWorker

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.1.154
• 6.6.108
• 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
• 6.12.16
• 6.12.17
• 6.12.18
• 6.12.19
• 6.12.20
• 6.12.21
• 6.12.22
• 6.12.23
• 6.12.24
• 6.12.25
• 6.12.26
• 6.12.27
• 6.12.28
• 6.12.29
• 6.12.30
• 6.12.31
• 6.12.32
• 6.12.33
• 6.12.34
• 6.12.35
• 6.12.36
• 6.12.37
• 6.12.38
• 6.12.39
• 6.12.40
• 6.12.41
• 6.12.42
• 6.12.43
• 6.12.44
• 6.12.45
• 6.12.46
• 6.12.47
• 6.12.48
• 6.12.49
• 6.16.0
• 6.16.1
• 6.16.2
• 6.16.3
• 6.16.4
• 6.16.5
• 6.16.6
• 6.16.7
• 6.16.8
• 6.16.9

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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