CVE-2026-64574
7.8 HIGHPublished 2026-08-05 · Updated 2026-08-08
AI risk analysis
- Summary
- The flaw involves a use-after-free vulnerability in the Linux kernel's mac80211 subsystem when adding new links during vif update. This can lead to dereferencing freed memory via debugfs files.
- Exploitability
- Exploitation requires runtime failure of drv_change_vif_links() on MLO drivers, making it moderately difficult but feasible with specific conditions.
- Blast radius
- If exploited, this could result in potential kernel crashes or privilege escalation due to memory corruption.
- Prioritized remediation
- Apply the patch from commit be1ba9ed221f to ensure new links' debugfs entries and links are properly removed before freeing containers.
Analysis generated locally by qwen2.5:7b-instruct (no data left the box). AI-assisted — verify against primary sources before acting.
NVD description
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
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
All references
- https://git.kernel.org/stable/c/0f7eaeb950adb77f71beb546e5ab30f90b41fe6f
- https://git.kernel.org/stable/c/329589417214d3b7221432e5b266ed2bba7ff674
- https://git.kernel.org/stable/c/901a73523e093beff123b54b1ceaf3113f18acc9
- https://git.kernel.org/stable/c/952c02b33f56207a160421bcd61e7ac53c9c59ae
- https://git.kernel.org/stable/c/c57d97f381306bbfba174e8f708419e007824e0c
Source data: NVD (nvd.nist.gov), public domain. Exploit-DB.ai adds local AI analysis for defensive use only.