CVE-2023-52501 ring-buffer: Do not attempt to read past "commit"
A flaw in the Linux kernel ring buffer allows out-of-bounds reads, potentially causing denial of service or information disclosure.
- 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-2023-52501?
CVE-2023-52501 is a high-severity memory corruption vulnerability in Linux kernel, published on 2 Mar 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:
ring-buffer: Do not attempt to read past "commit"
When iterating over the ring buffer while the ring buffer is active, the writer can corrupt the reader. There's barriers to help detect this and handle it, but that code missed the case where the last event was at the very end of the page and has only 4 bytes left.
The checks to detect the corruption by the writer to reads needs to see the length of the event. If the length in the first 4 bytes is zero then the length is stored in the second 4 bytes. But if the writer is in the process of updating that code, there's a small window where the length in the first 4 bytes could be zero even though the length is only 4 bytes. That will cause rb_event_length() to read the next 4 bytes which could happen to be off the allocated page.
To protect against this, fail immediately if the next event pointer is less than 8 bytes from the end of the commit (last byte of data), as all events must be a minimum of 8 bytes anyway.
Weakness: CWE-125
Which versions are affected by CVE-2023-52501?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2023-52501?
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-2023-52501 being exploited?
There is no known exploitation of CVE-2023-52501 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2023-52501, DEBIAN-CVE-2023-52501, GHSA-jfc7-9f46-xvqw, UBUNTU-CVE-2023-52501.