CVE-2026-74325

In the Linux kernel, the following vulnerability has been resolved: wifi: mt76: use kfree_rcu for offchannel link in mt76_put_vif_phy_link mt76_put_vif_phy_link() frees the offchannel mlink with plain kfree() after rcu_assign_pointer(NULL). However, rcu_assign_pointer only prevents future RCU readers from obtaining the pointer -- it does not wait for existing readers that already hold it via rcu_dereference. The TX datapath (e.g. mt7996_mac_write_txwi) dereferences mlink->wcid and mlink->idx under rcu_read_lock. If a TX softirq obtained the pointer via rcu_dereference just before the NULL assignment, it will dereference freed memory after the kfree. struct mt76_vif_link already contains an rcu_head field that is unused at this free site -- a developer oversight, since the adjacent kfree_rcu_mightsleep call for rx_sc in the same function shows the pattern was understood. Replace kfree(mlink) with kfree_rcu(mlink, rcu_head).

Affected products

Kernel, Linux, Linux-Allwinner-5.19, Linux-Aws, Linux-Aws-5.0, Linux-Aws-5.11, Linux-Aws-5.13, Linux-Aws-5.19

CVSS 3.1

7.8 HIGH

EPSS

0.1% (3th percentile)

NVD status

Received

Published

2026-08-15

No exploit for CVE-2026-74325 has been indexed yet. Our index is built from live traffic and upstream syncs, so this page can only say what it knows — not that no exploit exists.