CVE-2022-49948 vt: Clear selection before changing the font
A local attacker can trigger out-of-bounds memory access in the Linux kernel console by changing fonts while a selection is active, potentially causing a crash or leaking memory.
- 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-2022-49948?
CVE-2022-49948 is a high-severity memory corruption vulnerability in Linux kernel, published on 18 Jun 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:
vt: Clear selection before changing the font
When changing the console font with ioctl(KDFONTOP) the new font size can be bigger than the previous font. A previous selection may thus now be outside of the new screen size and thus trigger out-of-bounds accesses to graphics memory if the selection is removed in vc_do_resize().
Prevent such out-of-memory accesses by dropping the selection before the various con_font_set() console handlers are called.
Weakness: CWE-125
Which versions are affected by CVE-2022-49948?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2022-49948?
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-2022-49948 being exploited?
There is no known exploitation of CVE-2022-49948 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2022-49948, GHSA-r6pw-rw8p-5cr9, UBUNTU-CVE-2022-49948.