Linux Kernel mptcp allocation of resources

Summaryinfo

A vulnerability was found in Linux Kernel. It has been classified as critical. The impacted element is an unknown function of the component mptcp. The manipulation leads to allocation of resources. This vulnerability is uniquely identified as CVE-2026-80588. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability was found in Linux Kernel (unknown version) and classified as critical. This issue affects an unknown code block of the component mptcp. The manipulation with an unknown input leads to a allocation of resources vulnerability. Using CWE to declare the problem leads to 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. Impacted is availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: mptcp: reclaim forward-allocated memory on RX path errors After commit 9db5b3cec4ec ("mptcp: borrow forward memory from subflow"), errors in the receive path prior to queueing skbs into the receive queue do not trigger forward-allocated memory reclaiming. Prevent forward memory from growing unboundedly in pathological drop scenarios by explicitly reclaiming memory when skbs are dropped.

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2026-80588 since 08/26/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 08/26/2026). MITRE ATT&CK project uses the attack technique T1499 for this issue.

Applying the patch 473f1a5ab2abc98dd9e74b95b9c23c66c47535cc/8277f48a06d3aa1441f6d0b6998ccc0360d30ed8/41b49a8b914ec7dcb03eae93fb27f3c464078644 is able to eliminate this problem.

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Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

License

• open-source

Website

• Vendor: https://www.kernel.org/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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