Pivotal Concourse, most versions prior to 6.0.0, allows redirects to untrusted websites in its login flow. A remote unauthenticated attacker could convince a user to click on a link using the OAuth redirect link with an untrusted website and gain access to that userβs access token in Concourse. (This issue is similar to, but distinct from, CVE-2018-15798.)
https://tanzu.vmware.com/security/cve-2020-5409
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-5409