CVE-2023-22483 cmark-gfm Quadratic complexity bugs may lead to a denial of service

Low 3.5 Published 23 Jan 2023 Updated 10 Mar 2025

Attackers can cause denial of service in cmark-gfm by submitting inputs that trigger quadratic time complexity, exhausting resources.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2023-22483?

CVE-2023-22483 is a low-severity denial of service vulnerability in github cmark-gfm, published on 23 Jan 2023. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

cmark-gfm is GitHub's fork of cmark, a CommonMark parsing and rendering library and program in C. Versions prior to 0.29.0.gfm.7 are subject to several polynomial time complexity issues in cmark-gfm that may lead to unbounded resource exhaustion and subsequent denial of service. Various commands, when piped to cmark-gfm with large values, cause the running time to increase quadratically. These vulnerabilities have been patched in version 0.29.0.gfm.7.

Weakness: CWE-407, CWE-400

Which versions are affected by CVE-2023-22483?

It affects 1 product.

Products include Github Cmark-Gfm.

How do I fix CVE-2023-22483?

Upgrade to a fixed version.

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-2023-22483 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-22483 exists.

Sources

Also known as DEBIAN-CVE-2023-22483, GHSA-29g3-96g3-jg6c, UBUNTU-CVE-2023-22483.