CVE-2023-46136 (GCVE-0-2023-46136)

Vulnerability from cvelistv5 – Published: 2023-10-24 23:48 – Updated: 2026-05-20 22:17
VLAI
Title
Werkzeug vulnerable to high resource usage when parsing multipart/form-data containing a large part with CR/LF character at the beginning
Summary
Werkzeug is a comprehensive WSGI web application library. In versions on the 3.x branch prior to 3.0.1 and on the 2.x branch prior to 2.3.8, if an upload of a file that starts with CR or LF and then is followed by megabytes of data without these characters: all of these bytes are appended chunk by chunk into internal bytearray and lookup for boundary is performed on growing buffer. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests. This vulnerability has been patched in version 3.0.1 and 2.3.8.
Severity
8 (High)
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE
  • CWE-407 - Inefficient Algorithmic Complexity
  • CWE-400 - Uncontrolled Resource Consumption
Assigner
References
Impacted products
Vendor Product Version
pallets werkzeug Affected: >= 3.0.0, < 3.0.1
Affected: >= 2.0.0rc1, < 2.3.8
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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