CVE-2026-63957 USB: serial: safe_serial: fix memory corruption with small endpoint

Not scored Published Updated

A malicious USB device can trigger memory corruption in the Linux kernel safe_serial driver, potentially allowing local attackers to execute code or escalate privileges.

Exploited in the wild
Not known
Login needed
Not needed
Attackable
Local or same network only
Victim action needed
A user has to click or open something
Fix
Available

What is CVE-2026-63957?

CVE-2026-63957 is a memory corruption vulnerability in Linux, published on 19 Jul 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

Official description

In the Linux kernel, the following vulnerability has been resolved:

USB: serial: safe_serial: fix memory corruption with small endpoint

Make sure that the bulk-out buffer size is at least eight bytes to avoid user-controlled slab corruption in "safe" mode should a malicious device report a smaller size.

Which versions are affected by CVE-2026-63957?

How do I fix CVE-2026-63957?

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-2026-63957 being exploited?

There is no known exploitation of CVE-2026-63957 in the wild and no public exploit code.

Sources

Also known as BELL-CVE-2026-63957, DEBIAN-CVE-2026-63957, GHSA-6392-wc5j-gpp8, ROOT-OS-UBUNTU-2204-CVE-2026-63957, UBUNTU-CVE-2026-63957.

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