API Platform Core is a system to create hypermedia-driven REST and GraphQL APIs. Prior to 4.0.22 and 3.4.17, a GraphQL grant on a property might be cached with different objects. The ApiPlatform\GraphQl\Serializer\ItemNormalizer::isCacheKeySafe() method is meant to prevent the caching but the parent::normalize method that is called afterwards still creates the cache key and causes the issue. This vulnerability is fixed in 4.0.22 and 3.4.17.
https://github.com/api-platform/core/security/advisories/GHSA-428q-q3vv-3fq3
https://github.com/api-platform/core/releases/tag/v3.4.17
https://github.com/api-platform/core/commit/cba3acfbd517763cf320167250c5bed6d569696a
https://github.com/api-platform/core/commit/7af65aad13037d7649348ee3dcd88e084ef771f8