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CVE-2024-53981PYSEC-2026-1851GHSA-59G5-XGCQ-4QW3

python-multipart has a Denial of service (DoS) via deformation `multipart/form-data` boundary

Published
Last modified
published
Not listed in CISA KEV
Fix
Fixed in 0.0.18
None on Exploit-DB, Metasploit or GitHub
  • Exploitation: none
  • Automatable: yes
  • Technical impact: partial

Summary

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.

Timeline

  1. CVE published
  2. CISA SSVC assessment

    Exploitation: none · Automatable: yes · Technical impact: partial

  3. Record last updated

Affected versions

  • Kludex python-multipart

    fixed in 0.0.18

  • python-multipartPyPI

    fixed in 0.0.18

References 2

GitHub · Kludex/python-multipart