CVE-2026-98704 wifi: mac80211: keep fallback association elements alive
A use-after-free in the Linux kernel Wi-Fi subsystem allows attackers to execute code or cause denial of service via crafted association responses.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-98704?
CVE-2026-98704 is an use after free vulnerability in Linux, published on 18 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: keep fallback association elements alive
Associating to a non-transmitted MBSSID profile reads freed memory while determining the operating channel and applying HT capabilities.
When an association response omits WMM, HT, or VHT information, ieee80211_assoc_config_link() parses the cached BSS IEs and copies the missing element pointers out of that fallback parse. For a non-transmitted MBSSID profile those pointers refer to merged-profile storage owned by the parse object, and the fallback block frees that object at its end. The copied pointers are used afterwards to determine the operating channel, configure bandwidth, and apply HT capabilities.
Keep the fallback parse result alive until association setup finishes.
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Which versions are affected by CVE-2026-98704?
How do I fix CVE-2026-98704?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-98704 being exploited?
There is no known exploitation of CVE-2026-98704 in the wild and no public exploit code.
Sources
Also known as AZL-108771, BELL-CVE-2026-98704, DEBIAN-CVE-2026-98704, GHSA-vrf9-cxgg-qw6c, UBUNTU-CVE-2026-98704.