Open Redirect
Open redirect vulnerabilities allow attackers to redirect users from a trusted site to an arbitrary external URL. This is commonly exploited in phishing campaigns, OAuth token theft, and SSO bypass attacks.
Overview
Open redirects occur when an application accepts user-controlled input to determine a redirect destination without proper validation. Attackers craft URLs that appear to point to the trusted application but redirect victims to malicious sites. This is particularly dangerous in OAuth flows where redirect URIs can leak authorization codes.
Impact
Phishing attacks leveraging trusted domains, OAuth token theft, SSO bypass, credential harvesting.
Examples
Phishing Redirect
https://trusted-site.com/redirect?url=https://evil-site.com/login
Remediation
Validate redirect URLs against an allowlist, avoid user-controlled redirect parameters, use relative URLs, and display warnings before external redirects.
Validate redirect URLs against a strict allowlist
Use relative URLs for internal redirects
Do not pass redirect destinations as URL parameters
Display a warning page before external redirects
Related SuperClue scanner checks
These scanner checks look for signs of Open Redirect. What a scan can confirm from outside depends on your application.
Scan a domain you have verified with up to 350 modules, paid in credits.
See how website scanning works