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CVE PROGRAM SOURCE RECORD7.5 High

CVE-2026-28356

ReDoS in multipart 1.3.0 - `parse_options_header()`

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Status
Published
Published
Updated
Assigning organization
GitHub_M

Description

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.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

defnull multipart

  • >= 1.3.0, < 1.3.1affected
  • < 1.2.2affected

References