CVE-2021-41556
Summary
| CVE | CVE-2021-41556 |
|---|---|
| State | PUBLISHED |
| Assigner | mitre |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2022-07-28 21:15:08 UTC |
| Updated | 2026-05-29 20:16:21 UTC |
| Description | 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. |
Risk And Classification
Primary CVSS: v3.1 10 CRITICAL from [email protected]
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS: 0.026980000 probability, percentile 0.861480000 (date 2026-06-02)
Problem Types: CWE-125 | n/a | CWE-125 CWE-125 Out-of-bounds Read
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Primary | 10 | CRITICAL | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
| 3.1 | ADP | DECLARED | 10 | CRITICAL | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
| 3.1 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | Secondary | 10 | CRITICAL | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
ChangedConfidentiality
HighIntegrity
HighAvailability
HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Operating System | Fedoraproject | Fedora | 35 | All | All | All |
| Operating System | Fedoraproject | Fedora | 36 | All | All | All |
| Application | Squirrel-lang | Squirrel | All | All | All | All |
| Application | Squirrel-lang | Squirrel | All | All | All | All |
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| Squirrel Sandbox Escape allows Code Execution in Games and Cloud Services | af854a3a-2127-422b-91ae-364da2661108 | blog.sonarsource.com | Exploit, Third Party Advisory |
| Squirrel - The Programming Language | af854a3a-2127-422b-91ae-364da2661108 | www.squirrel-lang.org | Third Party Advisory |
| www.sonarsource.com/blog/squirrel-vm-sandbox-escape | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | www.sonarsource.com | |
| [SECURITY] Fedora 36 Update: squirrel-2.2.5-25.fc36 - package-announce - Fedora Mailing-Lists | af854a3a-2127-422b-91ae-364da2661108 | lists.fedoraproject.org | |
| check max member count in class · albertodemichelis/squirrel@23a0620 · GitHub | af854a3a-2127-422b-91ae-364da2661108 | github.com | Patch, Third Party Advisory |
| [SECURITY] Fedora 35 Update: squirrel-2.2.5-25.fc35 - package-announce - Fedora Mailing-Lists | af854a3a-2127-422b-91ae-364da2661108 | lists.fedoraproject.org | |
| [SECURITY] Fedora 36 Update: squirrel-2.2.5-25.fc36 - package-announce - Fedora Mailing-Lists | MITRE | lists.fedoraproject.org | |
| [SECURITY] Fedora 35 Update: squirrel-2.2.5-25.fc35 - package-announce - Fedora Mailing-Lists | MITRE | lists.fedoraproject.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.