Markdownify 1.2.0 - Persistent Cross-Site Scripting

Markdownify 1.2.0 contains a persistent cross-site scripting vulnerability that allows attackers to store malicious payloads within markdown files. Attackers can upload crafted markdown files with embedded scripts that execute when the file is opened, potentially enabling remote code execution.

python-markdownify (aka markdownify) before 0.14.1 allows large headline prefixes such as <h9999999> in addition to <h1> through <h6>. This causes memory consumption.