Impact

Any user making use of a wildcard relationship under the right hand branch of an exclusion or within an intersection operation will see Lookup/LookupResources return a resource as "accessible" if it is not accessible by virtue of the inclusion of the wildcard in the intersection or the right side of the exclusion.

For example, given schema:

definition user {}

definition resource {
   relation viewer: user
   relation banned: user | user:*
   permission view = viewer - banned
}

If user:* is placed into the banned relation for a particular resource, view should return false for all resources. in v1.3.0, the wildcard is ignored entirely in lookup's dispatch, resulting in the banned wildcard being ignored in the exclusion.

Workarounds

Don't make use of wildcards on the right side of intersections or within exclusions.

References

#358

For more information

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