URL Redirection to Untrusted Site ('Open Redirect')
Open redirect vulnerability in gluon/tools.py in Web2py 2.9.11 allows remote attackers to redirect users to arbitrary web sites and conduct phishing attacks via a URL in the parameter to user/logout.
CWE-601 - Open Redirect
An open redirect attack employs a URL parameter, HTML refresh tags, or a DOM based location change to exploit the trust of a vulnerable domain to direct the users to a malicious website. The attack could lead to higher severity vulnerabilities such as unauthorized access control, account takeover, XSS, and more.