Riskcovery

CVE-2023-46136

Werkzeug vulnerable to high resource usage when parsing multipart/form-data containing a large part with CR/LF character at the beginning

State
Published
Severity
8.0 High
Published
Oct 24, 2023
Updated
May 20, 2026
Reserved
Oct 16, 2023

Read the record on cve.org

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.

Scores

CVSSScoreVectorSource
3.18.0 HighCVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HGitHub_M

Weaknesses

  • CWE-407 Inefficient Algorithmic Complexity
  • CWE-400 Uncontrolled Resource Consumption

Affected Products

ProductVersions
werkzeugpallets
  • >= 3.0.0, < 3.0.1Affected
  • >= 2.0.0rc1, < 2.3.8Affected

References

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