Findings

CVE-2026-98422

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: reset the AP_VLAN tailroom counter on ifdown On ifup, AP_VLAN interfaces get crypto…

Published Oct 14, 2026

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: reset the AP_VLAN tailroom counter on ifdown On ifup, AP_VLAN interfaces get crypto_tx_tailroom_needed_cnt from the AP interface, but it's never decremented again unless the AP is also brought down. Thus, bringing the same AP_VLAN up again will increment the counter again and eventually hit the sanity check: WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt != master->crypto_tx_tailroom_needed_cnt); Reset it on ifdown to avoid that.

Timeline

Detection, updates, and resolution for this record.

  1. Oct 14, 2026 · Tenable CVE Database

    Detected

    In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: reset the AP_VLAN tailroom counter on ifdown On ifup, AP_VLAN interfaces get crypto_tx_tailroom_needed_cnt from the AP interface, but it's never decremented again unless the AP is also brought down. Thus, bringing the same AP_VLAN up again will increment the counter again and eventually hit the sanity check: WARN_O

Sources

  • CVE.orgCVE-2026-98422

    Official CVE identifier

    cve.org
  • Tenable CVE DatabaseCVE-2026-98422

    In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: reset the AP_VLAN tailroom counter on ifdown On ifup, AP_VLAN interfaces get crypto_tx_tailroom_needed_cnt from the AP interface, but it's never decremented again unless the AP is also brought down. Thus, bringing the same AP_VLAN up again will increment the counter again and eventually hit the sanity check: WARN_O

    tenable.com
CVE-2026-98422 · ZeroDay Findings