typed-rest-client is a library for Node Rest and Http Clients with typings for use with TypeScript. Users of the typed-rest-client library version 1.7.3 or lower are vulnerable to leak authentication data to 3rd parties. The flow of the vulnerability is as follows: First, send any request with "BasicCredentialHandler", "BearerCredentialHandler" or "PersonalAccessTokenCredentialHandler". Second, the target host may return a redirection (3xx), with a link to a second host. Third, the next request will use the credentials to authenticate with the second host, by setting the "Authorization" header. The expected behavior is that the next request will NOT set the "Authorization" header. The problem was fixed in version 1.8.0. There are no known workarounds.