CVE-2024-41091 tun: add missing verification for short frame
A missing length check in the Linux kernel TUN driver allows out-of-bounds access, potentially leading to system crashes or code execution.
- 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-2024-41091?
CVE-2024-41091 is a high-severity memory corruption vulnerability in Linux kernel, published on 29 Jul 2024. 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:
tun: add missing verification for short frame
The cited commit missed to check against the validity of the frame length in the tun_xdp_one() path, which could cause a corrupted skb to be sent downstack. Even before the skb is transmitted, the tun_xdp_one-->eth_type_trans() may access the Ethernet header although it can be less than ETH_HLEN. Once transmitted, this could either cause out-of-bound access beyond the actual length, or confuse the underlayer with incorrect or inconsistent header length in the skb metadata.
In the alternative path, tun_get_user() already prohibits short frame which has the length less than Ethernet header size from being transmitted for IFF_TAP.
This is to drop any frame shorter than the Ethernet header size just like how tun_get_user() does.
CVE: CVE-2024-41091
Weakness: CWE-125
Which versions are affected by CVE-2024-41091?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2024-41091?
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-2024-41091 being exploited?
There is no known exploitation of CVE-2024-41091 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2024-41091, DEBIAN-CVE-2024-41091, GHSA-x5q2-qqwh-x9rv, UBUNTU-CVE-2024-41091.