CVE-2026-64574

Status: UPDATED  |  Advisory ID: CVE-2026-64574

Key Details

Affected Products, Subsystems & Sectors

What to Know

In the Linux kernel, the following vulnerability has been resolved:

wifi: mac80211: tear down new links on vif update error path

When ieee80211_vif_update_links() adds new links it allocates a link

container for each and calls ieee80211_link_init() (which registers the

per-link debugfs files with file->private_data pointing into the container)

and ieee80211_link_setup(). If the subsequent drv_change_vif_links() fails,

the error path restores the old pointers and jumps to 'free', which frees

the new containers but never removes their debugfs entries or stops the

links. The debugfs files survive with file->private_data dangling at the

freed container, so a later open()+read() (e.g. link-1/txpower)

dereferences freed memory in ieee80211_if_read_link(), a use-after-free.

The removal path already dismantles links correctly via

ieee80211_tear_down_links(), which removes each link's keys and debugfs

entries and calls ieee80211_link_stop(); the add path on the error branch

does not. Commit be1ba9ed221f ("wifi: mac80211: avoid weird state in error

path") hardened this same error path for the link-removal case

(new_links == 0) but left the newly-added links' teardown unaddressed.

drv_change_vif_links() can fail at runtime on MLO drivers (internal

allocation / queue / firmware command failures).

Remove the new links' debugfs entries and stop them before freeing.

BUG: KASAN: slab-use-after-free in ieee80211_if_read_link (net/mac80211/debugfs_netdev.c:127)

Read of size 8 at addr ffff888011290000 by task exploit/145

Call Trace:

...

ieee80211_if_read_link (net/mac80211/debugfs_netdev.c:127)

short_proxy_read (fs/debugfs/file.c:373)

vfs_read (fs/read_write.c:572)

ksys_read (fs/read_write.c:716)

do_syscall_64 (arch/x86/entry/syscall_64.c:94)

entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)

...

Oops: general protection fault, probably for non-canonical address 0xdffffc000000000a

RIP: 0010:ieee80211_if_read_link (net/mac80211/debugfs_netdev.c:127)

Kernel panic - not syncing: Fatal exception (NVD)

What to Do

Monitor Linux's web page for any future patch releases.

References