cve.bz

CVE-2021-41556

10.0 criticalEPSS 2.9%

Critical (10.0). EPSS 2.9% chance of exploitation in the next 30 days.

sqclass.cpp in Squirrel through 2.2.5 and 3.x through 3.1 allows an out-of-bounds read (in the core interpreter) that can lead to Code Execution. If a victim executes an attacker-controlled squirrel script, it is possible for the attacker to break out of the squirrel script sandbox even if all dangerous functionality such as File System functions has been disabled. An attacker might abuse this bug to target (for example) Cloud services that allow customization via SquirrelScripts, or distribute malware through video games that embed a Squirrel Engine.

Severity

CVSS 3.1

10.0 critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS
2.9% chance of exploitation in the next 30 days; higher than 87% of CVEs (scores of 2026-10-31)
CWE
CWE-125
Published
Modified
Record from
the NVD, synced

Affected

References

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