PyPI: werkzeug
CVE-2023-23934
Safety vulnerability ID: SFTY-20230214-29712
Safety legacy ID: pyup.io-53326
Werkzeug 2.2.3 includes a fix for CVE-2023-23934: 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. https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q
Overview
Incorrect parsing of nameless cookies leads to __Host- cookies bypass
Advisory
Werkzeug 2.2.3 includes a fix for CVE-2023-23934: 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. https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q
How to Fix
Mitigation and Workarounds
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Vulnerable Functions
Functions linked to known vulnerabilities.
References
- https://getsafety.com/vulnerabilities/SFTY-20230214-29712/CVE-2023-23934
- https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-23934
- https://github.com/pallets/werkzeug/commit/cf275f42acad1b5950c50ffe8ef58fe62cdce028
- https://github.com/pallets/werkzeug/releases/tag/2.2.3
- https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q
- https://security.netapp.com/advisory/ntap-20230818-0003/
- https://www.debian.org/security/2023/dsa-5470
- https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q
- https://nvd.nist.gov/vuln/detail/CVE-2023-23934
- https://github.com/pallets/werkzeug/commit/cf275f42acad1b5950c50ffe8ef58fe62cdce028
- https://github.com/pallets/werkzeug/releases/tag/2.2.3
- https://www.debian.org/security/2023/dsa-5470
- https://github.com/pypa/advisory-database/tree/main/vulns/werkzeug/PYSEC-2023-57.yaml
- https://security.netapp.com/advisory/ntap-20230818-0003
- https://github.com/advisories/GHSA-px8h-6qxv-m22q
Verified by Safety
Our Cybersecurity Intelligence Team reviewed this vulnerability. We combine public data with our own research to find issues not yet reported to public sources.
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