CVE-2022-49326 rtl818x: Prevent using not initialized queues
A missing initialization check in the rtl818x wireless driver causes a kernel panic when handling specific packet priorities, leading to denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2022-49326?
CVE-2022-49326 is a medium-severity vulnerability in Linux kernel, published on 26 Feb 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:
rtl818x: Prevent using not initialized queues
Using not existing queues can panic the kernel with rtl8180/rtl8185 cards. Ignore the skb priority for those cards, they only have one tx queue. Pierre Asselin ([email protected]) reported the kernel crash in the Gentoo forum:
https://forums.gentoo.org/viewtopic-t-1147832-postdays-0-postorder-asc-start-25.html
He also confirmed that this patch fixes the issue. In summary this happened:
After updating wpa_supplicant from 2.9 to 2.10 the kernel crashed with a "divide error: 0000" when connecting to an AP. Control port tx now tries to use IEEE80211_AC_VO for the priority, which wpa_supplicants starts to use in 2.10.
Since only the rtl8187se part of the driver supports QoS, the priority of the skb is set to IEEE80211_AC_BE (2) by mac80211 for rtl8180/rtl8185 cards.
rtl8180 is then unconditionally reading out the priority and finally crashes on drivers/net/wireless/realtek/rtl818x/rtl8180/dev.c line 544 without this patch: idx = (ring->idx + skb_queue_len(&ring->queue)) % ring->entries
"ring->entries" is zero for rtl8180/rtl8185 cards, tx_ring[2] never got initialized.
Weakness: CWE-908
Which versions are affected by CVE-2022-49326?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2022-49326?
Apply the vendor's patch.
Is CVE-2022-49326 being exploited?
There is no known exploitation of CVE-2022-49326 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2022-49326, GHSA-3v9q-m8x4-6crj, UBUNTU-CVE-2022-49326.