CVE-2021-47669 can: vxcan: vxcan_xmit: fix use after free bug
A use-after-free bug in the Linux kernel's vxcan driver allows attackers to potentially execute code or cause a system crash.
- 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-2021-47669?
CVE-2021-47669 is a high-severity use after free vulnerability in Linux kernel, published on 17 Apr 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:
can: vxcan: vxcan_xmit: fix use after free bug
After calling netif_rx_ni(skb), dereferencing skb is unsafe. Especially, the canfd_frame cfd which aliases skb memory is accessed after the netif_rx_ni().
Weakness: CWE-416
Which versions are affected by CVE-2021-47669?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2021-47669?
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-2021-47669 being exploited?
There is no known exploitation of CVE-2021-47669 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2021-47669, GHSA-677p-h2hj-9j82, UBUNTU-CVE-2021-47669.