Multiple caveats on resources of the same type can result in no permission when permission is expected

Vulnerability Description

spicedb is an Open Source, Google Zanzibar-inspired permissions database to enable fine-grained authorization for customer applications. Multiple caveats over the same indirect subject type on the same relation can result in no permission being returned when permission is expected. If the resource has multiple groups, and each group is caveated, it is possible for the returned permission to be "no permission" when permission is expected. Permission is returned as NO_PERMISSION when PERMISSION is expected on the CheckPermission API. This issue has been addressed in release version 1.35.3. Users are advised to upgrade. Users unable to upgrade should not use caveats or avoid the use of caveats on an indirect subject type with multiple entries.

References

• https://github.com/authzed/spicedb/security/advisories/GHSA-jhg6-6qrx-38mr
• https://github.com/authzed/spicedb/commit/d4ef8e1dbce1eafaf25847f4c0f09738820f5bf2