The example code for the digest authentication functionality (httpauthentication.rb) in Ruby on Rails before 2.3.3 defines an authenticateorrequestwithhttpdigest block that returns nil instead of false when the user does not exist, which allows context-dependent attackers to bypass authentication for applications that are derived from this example by sending an invalid username without a password.
{ "nvd_published_at": "2009-07-10T15:30:00Z", "cwe_ids": [ "CWE-287" ], "severity": "CRITICAL", "github_reviewed": true, "github_reviewed_at": "2020-06-16T21:56:22Z" }