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vulnerability

Debian: CVE-2023-23934: python-werkzeug -- security update

Severity
2
CVSS
(AV:A/AC:H/Au:N/C:N/I:P/A:N)
Published
Feb 14, 2023
Added
Mar 1, 2023
Modified
Mar 30, 2026

Description

Werkzeug is a comprehensive WSGI web application library. Browsers may allow "nameless" cookies that look like `=value` instead of `key=value`. A vulnerable browser may allow a compromised application on an adjacent subdomain to exploit this to set a cookie like `=__Host-test=bad` for another subdomain. Werkzeug prior to 2.2.3 will parse the cookie `=__Host-test=bad` as __Host-test=bad`. If a Werkzeug application is running next to a vulnerable or malicious subdomain which sets such a cookie using a vulnerable browser, the Werkzeug application will see the bad cookie value but the valid cookie key. The issue is fixed in Werkzeug 2.2.3.

Solution

debian-upgrade-python-werkzeug
Title
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