CVE-2021-21899 Memory corruption in LibreCAD

What is CVE-2021-21899?

CVE-2021-21899 is a high-severity memory corruption vulnerability in Debian Debian Linux, published on 19 Nov 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

A code execution vulnerability exists in the dwgCompressor::copyCompBytes21 functionality of LibreCad libdxfrw 2.2.0-rc2-19-ge02f3580. A specially-crafted .dwg file can lead to a heap buffer overflow. An attacker can provide a malicious file to trigger this vulnerability.

Weakness: CWE-787, CWE-119

Which versions are affected by CVE-2021-21899?

It affects 3 products.

Products include Debian Debian Linux, Fedoraproject Fedora, Librecad Libdxfrw.

How do I fix CVE-2021-21899?

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-2021-21899 being exploited?

There is no known exploitation of CVE-2021-21899 in the wild and no public exploit code.

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All Debian Debian Linux vulnerabilities

Sources

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

Also known as DEBIAN-CVE-2021-21899, GHSA-xwm9-c4jc-crcp, UBUNTU-CVE-2021-21899.