CVE-2026-55405: LangChain4j: SQL injection via metadata filters in langchain4j-mariadb and langchain4j-pgvector

The MariaDB and pgvector embedding stores build metadata-filter SQL by string-concatenating filter keys (and, in MariaDB, string values) directly into the query without adequate escaping. A crafted metadata key in EmbeddingSearchRequest.filter() can break out of its SQL context and inject arbitrary SQL into the statements executed by the stores’ search and removeAll(Filter) operations.