CVE-2026-85664 [HIGH] – Chroma 1.5.9 fails to validate maximum bounds on HNSW index parameters max_neighbors, ef_c

Chroma 1.5.9 fails to validate maximum bounds on HNSW index parameters max_neighbors, ef_construction, and ef_search in collection-create requests. Unauthenticated attackers can supply arbitrarily large parameter values to exhaust server memory and cause denial of service during index compaction.