VULNERABILITY INTELLIGENCE

CVE-2026-42561

CVSS score7.5 HIGH
EPSS probability0.74%
CISA KEVNot currently listed
Published2026-05-13
Last modified2026-10-26
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Description

Python-Multipart is a streaming multipart parser for Python. Prior to 0.0.27, python-multipart has a denial of service vulnerability in multipart part header parsing. When parsing multipart/form-data, MultipartParser previously had no limit on the number of part headers or the size of an individual part header. An attacker could send a request with either many repeated headers without terminating the header block or a single very large header value, causing excessive CPU work before request rejection or completion. This vulnerability is fixed in 0.0.27.

Weakness classification

  • security-advisories@github.com: CWE-770
  • 0b0ca135-0b70-47e7-9f44-1890c2a1c46c: CWE-606

Primary references