CVE-2021-41556 Memory corruption in n/a

What is CVE-2021-41556?

CVE-2021-41556 is a critical memory corruption vulnerability in Fedoraproject Fedora, published on 28 Jul 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official 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.

Weakness: CWE-125

Which versions are affected by CVE-2021-41556?

It affects 2 products.

Products include Fedoraproject Fedora, Squirrel-Lang Squirrel.

How do I fix CVE-2021-41556?

Upgrade to a fixed version.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2021-41556 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-41556 exists.

Other vulnerabilities in Fedoraproject Fedora

• CVE-2024-4577 PHP-CGI OS Command Injection Exploited Critical 9.8
• CVE-2021-39226 Grafana Authentication Bypass Exploited Critical 9.8
• CVE-2019-5544 VMware ESXi and Horizon DaaS OpenSLP Heap-Based Buffer Overflow Exploited Critical 9.8
• CVE-2024-4947 Google Chromium V8 Type Confusion Exploited Critical 9.6
• CVE-2024-4671 Google Chromium Visuals Use-After-Free Exploited Critical 9.6

All Fedoraproject Fedora vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2021-41556, GHSA-cm28-mc8h-9h49, MGASA-2023-0150, UBUNTU-CVE-2021-41556, openSUSE-SU-2023:0080-1, openSUSE-SU-2024:12611-1.