CVE-2026-46234 vsock: fix buffer size clamping order
A logic error in Linux kernel vsock buffer size clamping allows memory boundaries to be bypassed, potentially leading to resource exhaustion or instability.
- 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-2026-46234?
CVE-2026-46234 is a high-severity vulnerability in Linux kernel, published on 28 May 2026. 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:
vsock: fix buffer size clamping order
In vsock_update_buffer_size(), the buffer size was being clamped to the maximum first, and then to the minimum. If a user sets a minimum buffer size larger than the maximum, the minimum check overrides the maximum check, inverting the constraint.
This breaks the intended socket memory boundaries by allowing the vsk->buffer_size to grow beyond the configured vsk->buffer_max_size.
Fix this by checking the minimum first, and then the maximum. This ensures the buffer size never exceeds the buffer_max_size.
Weakness: CWE-787
Which versions are affected by CVE-2026-46234?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-46234?
Apply the vendor's patch.
Is CVE-2026-46234 being exploited?
There is no known exploitation of CVE-2026-46234 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-89058, BELL-CVE-2026-46234, DEBIAN-CVE-2026-46234, GHSA-jc98-98jj-62cp, ROOT-OS-DEBIAN-11-CVE-2026-46234, ROOT-OS-DEBIAN-12-CVE-2026-46234 and 3 more.