When gRPC HTTP2 stack raised a header size exceeded error, it skipped parsing the rest of the HPACK frame. This caused any HPACK table mutations to also be skipped, resulting in a desynchronization of HPACK tables between sender and receiver. If leveraged, say, between a proxy and a backend, this could lead to requests from the proxy being interpreted as containing headers from different proxy clients - leading to an information leak that can be used for privilege escalation or data exfiltration. We recommend upgrading beyond the commit contained in https://github.com/grpc/grpc/pull/32309 https://github.com/grpc/grpc/pull/32309
Created flatbuffers tracking bugs for this issue: Affects: fedora-all [bug 2214465] Created grpc tracking bugs for this issue: Affects: fedora-all [bug 2214466] Affects: openstack-rdo [bug 2214467]