CVE-2020-27818 Denial of service in pngcheck

What is CVE-2020-27818?

CVE-2020-27818 is a low-severity denial of service vulnerability in Debian Debian Linux, published on 8 Dec 2020. 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

A flaw was found in the check_chunk_name() function of pngcheck-2.4.0. An attacker able to pass a malicious file to be processed by pngcheck could cause a temporary denial of service, posing a low risk to application availability.

Weakness: CWE-125, CWE-120

Which versions are affected by CVE-2020-27818?

It affects 4 products.

Products include Debian Debian Linux, Fedoraproject Extra Packages for Enterprise Linux, Fedoraproject Fedora, Libpng Pngcheck.

How do I fix CVE-2020-27818?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2020-27818 being exploited?

There is no known exploitation of CVE-2020-27818 in the wild and no public exploit code.

Public exploit code: 1 proofs of concept on GitHub.

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• 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-2020-27818, DLA-3032-1, GHSA-xjm9-9gr6-gcpx, UBUNTU-CVE-2020-27818, openSUSE-SU-2020:2177-1, openSUSE-SU-2020:2198-1 and 3 more.