multipart is a fast multipart/form-data parser for python. Prior to 1.2.2, 1.3.1 and 1.4.0-dev, the parse_options_header() function in multipart.py uses a regular expression with an ambiguous alternation, which can cause exponential backtracking (ReDoS) when parsing maliciously crafted HTTP or multipart segment headers. This can be abused for denial of service (DoS) attacks against web applications using this library to parse request headers or multipart/form-data streams. The issue is fixed in 1.2.2, 1.3.1 and 1.4.0-dev.
References
Configurations
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History
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Information
Published : 2026-03-12 17:16
Updated : 2026-03-12 21:07
NVD link : CVE-2026-28356
Mitre link : CVE-2026-28356
CVE.ORG link : CVE-2026-28356
JSON object : View
Products Affected
No product.
CWE
CWE-1333
Inefficient Regular Expression Complexity
