GHSA-hjph-f4mc-wx4c: Duplicate Advisory: Mistune has a ReDoS in LINK_TITLE_RE that allows denial of service via crafted Markdown input

Denial-of-Service (DoS) vulnerability in the Mistune Markdown parser. The issue occurs when processing specially crafted reference links, which can cause excessive parsing and CPU consumption, leading to application hangs.

Function affected: parse_link_title() in helpers.py Issue: Malformed reference links cause excessive backtracking and parsing loops. Impact: Remote attackers can submit malicious Markdown to hang processes, causing service unavailability.