VLAN Tag Processing Vulnerability in Linux Kernel

CVE-2026-80906

What is CVE-2026-80906?

A vulnerability exists in the Linux kernel's handling of VLAN-tagged frames during packet processing. When processing a VLAN-tagged frame, the network header is incorrectly set, which leads to misinterpretation of the encapsulated EtherType. This issue occurs due to the order of function calls that advance pointers in the packet structure, resulting in the transport header remaining uninitialized. The flaw could lead to errors in packet dissection, impacting the handling of network traffic. A fix has been implemented to rearrange the processing sequence, allowing for accurate reading of the VLAN header and correct advancement to the inner protocol header.

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