CVE-2026-8258: Squirrel sqstdstring.cpp validate_format stack-based overflow

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-11 · updated 2026-07-23
Weakness: CWE-119

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.

Affected products

Squirrel: 3.0, 3.1, 3.2

References

https://github.com/albertodemichelis/squirrel/issues/325
https://github.com/biniamf/pocs/tree/main/squirrel-validate_format-memcpy-oob
https://vuldb.com/submit/809873
https://vuldb.com/vuln/362555
https://vuldb.com/vuln/362555/cti
https://github.com/albertodemichelis/squirrel/issues/325

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