Unauthenticated 'display name' information leak on enumeration of login names

Disclosed: 2020-03-01 14:01:16 By frankspierings To nextcloud
Medium
Vulnerability Details
- I reported this last week through email, but I didn't receive any response so that is why I report this once more. - This is probably not considered as a real security vulnerability, but my customers would like to see this fixed, therefore I report it. Problem: It is possible to get a users display name by knowing their login name. In our environment this results in a users full name. No credentials are required. (The login name could be either leaked or brute forced.) Reproduce: Browse (unauthenticated) to /index.php/avatar/<USERNAME>/abc. Replace <USERNAME> with a valid user login name. Fix: I personally would only allow this information to be disclosed when te requestor is authenticated.
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Report Stats
  • Report ID: 237232
  • State: Closed
  • Substate: resolved
  • Upvotes: 4
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