CVE-2021-47040 io_uring: fix overflows checks in provide buffers
An integer overflow in the Linux kernel's io_uring provide buffers function allows attackers to potentially execute arbitrary code or escalate privileges.
- 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-2021-47040?
CVE-2021-47040 is a high-severity vulnerability in Linux kernel, published on 28 Feb 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:
io_uring: fix overflows checks in provide buffers
Colin reported before possible overflow and sign extension problems in io_provide_buffers_prep(). As Linus pointed out previous attempt did nothing useful, see d81269fecb8ce ("io_uring: fix provide_buffers sign extension").
Do that with help of check_<op>_overflow helpers. And fix struct io_provide_buf::len type, as it doesn't make much sense to keep it signed.
Weakness: CWE-120
Which versions are affected by CVE-2021-47040?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2021-47040?
Apply the vendor's patch.
Is CVE-2021-47040 being exploited?
There is no known exploitation of CVE-2021-47040 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2021-47040, GHSA-phvq-9637-vp75, UBUNTU-CVE-2021-47040.