CVE-2026-3388: Squirrel · Uncontrolled Recursion
Affects SquirrelSource CVE Database V5
Public exploit available · CVSS 4.8 Medium.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 8% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:PExploitation evidence
Disclosed: evidence found.
CVE published 1 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: evidence found.
CVSS exploit maturity: proof of concept public
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CVSS vector, the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Squirrel | Affected
| Fixed in– |
GitHubalbertodemichelis/squirrelpkg:github/albertodemichelis/squirrelOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
To mitigate CVE-2026-3388, organizations should first restrict local access to systems running Squirrel to trusted users only, minimizing the risk of local exploitation. Implement strict access controls and monitoring to detect unusual crashes or recursion-related failures in applications embedding Squirrel. If feasible, disable or sandbox scripting features that utilize the vulnerable compiler functions to limit exposure. Developers should review and audit any input passed to the SQCompiler::Factor and UnaryOP functions to ensure it cannot be manipulated to cause recursion loops. Until an official patch is released, consider applying custom code fixes or workarounds such as input validation or recursion depth limits within the Squirrel embedding environment. Additionally, maintain up-to-date backups and prepare incident response plans for potential denial of service scenarios. Monitor the Squirrel project and vulnerability databases for any forthcoming patches or updates.
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.