Out-of-bounds Write Affecting python-werkzeug package, versions <3.0.1-2


Severity

Recommended
0.0
high
0
10

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Threat Intelligence

EPSS
1.07% (61st percentile)

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  • Snyk IDSNYK-DEBIAN14-PYTHONWERKZEUG-11765849
  • published10 Aug 2025
  • disclosed25 Oct 2023

Introduced: 25 Oct 2023

CVE-2023-46136  (opens in a new tab)
CWE-787  (opens in a new tab)

How to fix?

Upgrade Debian:14 python-werkzeug to version 3.0.1-2 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream python-werkzeug package and not the python-werkzeug package as distributed by Debian. See How to fix? for Debian:14 relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1