Linux Kernel Vulnerability in AP_VLAN Management by Linux Foundation

CVE-2026-98422

What is CVE-2026-98422?

A vulnerability exists in the Linux kernel regarding the handling of AP_VLAN interfaces during state changes. Specifically, when the AP_VLAN interface is taken down (ifdown), the crypto_tx_tailroom_needed_cnt is not decremented properly, leading to potential inconsistencies. If the same AP_VLAN interface is brought back up (ifup), the counter is incorrectly incremented, which can trigger a sanity check warning. This behavior can affect the performance and reliability of network communications, highlighting the need for proper management of interface state changes.

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