Dgraph: DQL Injection via unvalidated regexp filter argument in GraphQL query rewriter

Dgraph is an open source distributed GraphQL database. Prior to 25.3.8, maybeQuoteArg in graphql/resolve/query_rewriter.go passes regexp filter strings into generated DQL without quoting or validating the /pattern/flags form, allowing crafted GraphQL query or mutation filters to inject DQL operators, disclose unintended nodes, or expand modification and deletion targets. This issue is fixed in version 25.3.8.