PYSEC-2023-57

Dashboard / Vulnerabilities / PYSEC-2023-57

PYSEC-2023-57

Summary:

Details: 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.

References: https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q, https://github.com/pallets/werkzeug/commit/cf275f42acad1b5950c50ffe8ef58fe62cdce028, https://github.com/pallets/werkzeug/releases/tag/2.2.3