Description
Joomla! Core is prone to an open redirect vulnerability because the application fails to properly validate user-supplied input. Exploiting this issue may allow attackers to redirect users to arbitrary web sites and conduct phishing attacks; other attacks are also possible. Joomla! Core versions 3.x.x ranging from 3.0.0 and up to and including 3.9.20 are vulnerable.
Remediation
Update to Joomla! Core version 3.9.21 or latest
References
Related Vulnerabilities
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