CVE-2026-92791

Description

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.

References

• https://github.com/uber/kraken
• https://github.com/uber/kraken/blob/v0.1.27/build-index/tagserver/server.go#L128-L129
• https://github.com/uber/kraken/blob/v0.1.27/lib/backend/namepath/pather.go#L78-L84
• https://github.com/uber/kraken/blob/v0.1.27/lib/backend/testfs/server.go#L165-L173
• https://github.com/uber/kraken/issues/645