python-multipart vulnerable to content-type header Regular expression Denial of Service
At a glance
Severity
HIGH 7.5
EPSS
EPSS 1.52 % · percentile 74 (2026-10-27)
State
PUBLISHED
Published
Updated
Assigner
GitHub_M
NVD status
Analyzed
Description
`python-multipart` is a streaming multipart parser for Python. When using form data, `python-multipart` uses a Regular Expression to parse the HTTP `Content-Type` header, including options. An attacker could send a custom-made `Content-Type` option that is very difficult for the RegEx to process, consuming CPU resources and stalling indefinitely (minutes or more) while holding the main event loop. This means that process can't handle any more requests, leading to regular expression denial of service. This vulnerability has been patched in version 0.0.7.
PYSEC-2024-38 — FastAPI is a web framework for building APIs with Python 3.8+ based on standard Python type hints. When using form data, `python-multipart` uses a Regular Expre
PYSEC-2026-1850 — python-multipart vulnerable to Content-Type Header ReDoS
