CVE-2026-8258 Squirrel sqstdstring.cpp validate_format stack-based overflow
A local attacker can trigger a stack-based buffer overflow in the Squirrel library's string validation, potentially leading to code execution or denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-8258?
CVE-2026-8258 is a medium-severity memory corruption vulnerability in Squirrel, published on 11 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
A flaw has been found in Squirrel up to 3.2. Impacted is the function validate_format in the library sqstdlib/sqstdstring.cpp. Executing a manipulation can lead to stack-based buffer overflow. The attack can only be executed locally. The exploit has been published and may be used. The project was informed of the problem early through an issue report but has not responded yet.
Which versions are affected by CVE-2026-8258?
How do I fix CVE-2026-8258?
No fix has been published for CVE-2026-8258 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-8258 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-8258 exists.
Sources
Also known as DEBIAN-CVE-2026-8258, GHSA-fff5-x34w-4v72, UBUNTU-CVE-2026-8258.