CVE-2023-53802 wifi: ath9k: htc_hst: free skb in ath9k_htc_rx_msg() if there is no callback function
A memory leak in the ath9k HTC driver allows attackers to cause denial of service by sending crafted Wi-Fi packets.
- 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-2023-53802?
CVE-2023-53802 is a memory corruption vulnerability in Linux, published on 9 Dec 2025. 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: ath9k: htc_hst: free skb in ath9k_htc_rx_msg() if there is no callback function
It is stated that ath9k_htc_rx_msg() either frees the provided skb or passes its management to another callback function. However, the skb is not freed in case there is no another callback function, and Syzkaller was able to cause a memory leak. Also minor comment fix.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Which versions are affected by CVE-2023-53802?
How do I fix CVE-2023-53802?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2023-53802 being exploited?
There is no known exploitation of CVE-2023-53802 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2023-53802, DEBIAN-CVE-2023-53802, GHSA-47hx-9qjp-4jqg, UBUNTU-CVE-2023-53802.