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.
History

Wed, 13 May 2026 22:45:00 +0000

Type Values Removed Values Added
First Time appeared Kludex
Kludex python-multipart
Vendors & Products Kludex
Kludex python-multipart

Wed, 13 May 2026 21:15:00 +0000

Type Values Removed Values Added
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.
Title Python-Multipart: Denial of Service via unbounded multipart part headers
Weaknesses CWE-770
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-05-13T20:55:11.767Z

Reserved: 2026-04-28T16:56:50.192Z

Link: CVE-2026-42561

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-05-13T21:16:47.070

Modified: 2026-05-13T21:16:47.070

Link: CVE-2026-42561

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-05-13T22:30:06Z