CVE-2021-27347 Use after free in n/a

What is CVE-2021-27347?

CVE-2021-27347 is a medium-severity use after free vulnerability in Debian Debian Linux, published on 10 Jun 2021. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

Official description

Use after free in lzma_decompress_buf function in stream.c in Irzip 0.631 allows attackers to cause Denial of Service (DoS) via a crafted compressed file.

Weakness: CWE-416

Which versions are affected by CVE-2021-27347?

It affects 2 products.

Products include Debian Debian Linux, Long Range Zip Project Long Range Zip.

How do I fix CVE-2021-27347?

Upgrade to a fixed version.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2021-27347 being exploited?

There is no known exploitation of CVE-2021-27347 in the wild and no public exploit code.

Other vulnerabilities in Debian Debian Linux

• CVE-2015-3306 ProFTPD Improper Access Control Exploited Critical 10.0
• CVE-2025-49113 RoundCube Webmail Deserialization of Untrusted Data Exploited Critical 9.9
• CVE-2026-24061 GNU InetUtils Argument Injection Exploited Critical 9.8
• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

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

Also known as DEBIAN-CVE-2021-27347, GHSA-664h-5fq8-8969, UBUNTU-CVE-2021-27347.