CVE-2026-53539

Python-Multipart is a streaming multipart parser for Python. Prior to 0.0.30, when parsing application/x-www-form-urlencoded bodies, QuerystringParser located the field separator with a two step lookup: it first scanned the entire remaining buffer for &, and only when no & existed anywhere ahead...

Inefficient Algorithmic Complexity

Overview python-multipart is an A streaming multipart parser for Python Affected versions of this package are vulnerable to Inefficient Algorithmic Complexity in the QuerystringParser function when parsing application/x-www-form-urlencoded bodies containing semicolon-separated fields. An attacker...