Uber Kraken through 0.1.29 fails to validate the tag parameter in the /tags/{tag} endpoint, allowing unauthenticated attackers to traverse outside the configured storage root. Attackers can use percent-encoded parent-directory segments in the tag parameter to read arbitrary files accessible to the testfs backend process.

Uber Kraken through 0.1.29 fails to validate the tag parameter in the /tags/{tag} endpoint, allowing unauthenticated attackers to traverse outside the configured storage root. Attackers can use percent-encoded parent-directory segments in the tag parameter to read arbitrary files accessible to the testfs backend process.