CVE-2026-3388 Squirrel sqcompiler.cpp UnaryOP recursion
A local attacker can cause a denial of service via uncontrolled recursion in the Squirrel scripting library's compiler.
- 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-2026-3388?
CVE-2026-3388 is a medium-severity denial of service vulnerability in Squirrel, published on 1 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
A vulnerability was found in Squirrel up to 3.2. This affects the function SQCompiler::Factor/SQCompiler::UnaryOP of the file squirrel/sqcompiler.cpp. Performing a manipulation results in uncontrolled recursion. The attack needs to be approached locally. The exploit has been made public and could 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-2026-3388?
It affects 1 product.
Products include Squirrel-Lang Squirrel.
How do I fix CVE-2026-3388?
No fix has been published for CVE-2026-3388 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-3388 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-3388 exists.
Other vulnerabilities in Squirrel
Sources
Also known as DEBIAN-CVE-2026-3388, GHSA-px8q-3qhf-3h43, UBUNTU-CVE-2026-3388.