VULNERABILITY INTELLIGENCE

CVE-2023-46136

CVSS score8 HIGH
EPSS probability1.29%
CISA KEVNot currently listed
Published2023-10-25
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Description

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.

Weakness classification

  • CWE-400: Uncontrolled Resource Consumption
  • CWE-407: Inefficient Algorithmic Complexity
  • CWE-787: Out-of-bounds Write

Primary references