What’s Vulnerable › Vulnerabilities

CVE-2021-21337: URL Redirection to Untrusted Site ('Open Redirect') in Products.PluggableAuthService

• Severity: medium (CVSS 6.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 8.4% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2021-03-08 · updated 2026-06-17
• Weakness: CWE-601

Description

Products.PluggableAuthService is a pluggable Zope authentication and authorization framework. In Products.PluggableAuthService before version 2.6.0 there is an open redirect vulnerability. A maliciously crafted link to the login form and login functionality could redirect the browser to a different website. The problem has been fixed in version 2.6.1. Depending on how you have installed Products.PluggableAuthService, you should change the buildout version pin to `2.6.1` and re-run the buildout, or if you used `pip` simply do `pip install "Products.PluggableAuthService>=2.6.1".

Affected products

• zopefoundation Products.PluggableAuthService: before 2.6.1 — fixed in 2.6.1

How to fix

Upgrade to a fixed version: zopefoundation Products.PluggableAuthService 2.6.1. Check the vendor advisory for mitigations.

References

• http://packetstormsecurity.com/files/162911/Products.PluggableAuthService-2.6.0-Open-Redirect.html
• https://github.com/zopefoundation/Products.PluggableAuthService/commit/7eead067898852ebd3e0f143bc51295928528dfa
• https://github.com/zopefoundation/Products.PluggableAuthService/security/advisories/GHSA-p44j-xrqg-4xrr
• https://pypi.org/project/Products.PluggableAuthService/
• http://packetstormsecurity.com/files/162911/Products.PluggableAuthService-2.6.0-Open-Redirect.html
• https://github.com/zopefoundation/Products.PluggableAuthService/commit/7eead067898852ebd3e0f143bc51295928528dfa
• https://github.com/zopefoundation/Products.PluggableAuthService/security/advisories/GHSA-p44j-xrqg-4xrr
• https://pypi.org/project/Products.PluggableAuthService/

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