Linux Kernel net tcf_pedit_act infinite loop

Summaryinfo

A vulnerability identified as critical has been detected in Linux Kernel. Affected by this vulnerability is the function tcf_pedit_act of the component net. The manipulation leads to infinite loop. This vulnerability is documented as CVE-2026-46331. There is not any exploit available. Applying a patch is the recommended action to fix this issue.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel (affected version not known). This issue affects the function tcf_pedit_act of the component net. The manipulation with an unknown input leads to a infinite loop vulnerability. Using CWE to declare the problem leads to CWE-835. The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop. Impacted is availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: net/sched: fix pedit partial COW leading to page cache corruption tcf_pedit_act() computes the COW range for skb_ensure_writable() once before the key loop using tcfp_off_max_hint, but the hint does not account for the runtime header offset added by typed keys. This can leave part of the write region un-COW'd. Fix by moving skb_ensure_writable() inside the per-key loop where the actual write offset is known, and add overflow checking on the offset arithmetic. For negative offsets (e.g. Ethernet header edits at ingress), use skb_cow() to COW the headroom instead. Guard offset_valid() against INT_MIN, where negation is undefined.

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2026-46331 since 05/13/2026. Technical details are known, but no exploit is available.

Applying the patch 899ee91156e57784090c5565e4f31bd7dbffbc5a is able to eliminate this problem. The bugfix is ready for download at git.kernel.org.

The vulnerability is also documented in the databases at EUVD (EUVD-2026-37039) and CERT Bund (WID-SEC-2026-1938). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

• Open Source Linux Kernel

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

License

• open-source

Website

• Vendor: https://www.kernel.org/

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Entryinfo

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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