CVE-2024-53981: Kludex Python-Multipart

High severity, CVSS 7.5. EPSS: 0.6% chance of exploitation in the next 30 days.

python-multipart is a streaming multipart parser for Python. When parsing form data, python-multipart skips line breaks (CR \r or LF \n) in front of the first boundary and any tailing bytes after the last boundary. This happens one byte at a time and emits a log event each time, which may cause excessive logging for certain inputs. An attacker could abuse this by sending a malicious request with lots of data before the first or after the last boundary, causing high CPU load and stalling the processing thread for a significant amount of time. In case of ASGI application, this could stall the event loop and prevent other requests from being processed, resulting in a denial of service (DoS). This vulnerability is fixed in 0.0.18.

Affected products

• Kludex Python-Multipart: before 0.0.18 (fixed in 0.0.18)

Published 2024-12-02. Last modified 2026-06-17.