Linux Kernel up to 6.12.57/6.17.7 tcp dst_dev_rcu use after free

Summaryinfo

A vulnerability classified as critical was found in Linux Kernel up to 6.12.57/6.17.7. The impacted element is the function dst_dev_rcu of the component tcp. Such manipulation leads to use after free. This vulnerability is listed as CVE-2025-68188. There is no available exploit. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 6.12.57/6.17.7. Affected by this issue is the function dst_dev_rcu of the component tcp. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: tcp: use dst_dev_rcu() in tcp_fastopen_active_disable_ofo_check() Use RCU to avoid a pair of atomic operations and a potential UAF on dst_dev()->flags.

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2025-68188 since 12/16/2025. The exploitation is known to be easy. 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 02/21/2026).

The vulnerability scanner Nessus provides a plugin with the ID 298924 (SUSE SLES12 : Recommended update for initial livepatch (SUSE-SU-2026:0473-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.12.58 or 6.17.8 eliminates this vulnerability. Applying the patch bc2b881a0896c111c1041d8bb1f92a3b3873ace5/06da08d9355bf8e2070459bbedbe372ccc02cc0e/b62a59c18b692f892dcb8109c1c2e653b2abc95c 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 (298924) and CERT Bund (WID-SEC-2025-2868). 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
• Open Source Linux Kernel

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
• 6.12.16
• 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
• 6.12.50
• 6.12.51
• 6.12.52
• 6.12.53
• 6.12.54
• 6.12.55
• 6.12.56
• 6.12.57
• 6.17.0
• 6.17.1
• 6.17.2
• 6.17.3
• 6.17.4
• 6.17.5
• 6.17.6
• 6.17.7

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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