SECURITY UPDATE: Heap buffer overflow in ngx_http_grpc_module when
proxying oversized headers to a gRPC/HTTP/2 upstream
debian/patches/CVE-2026-42055.patch: reject request line and header
fields longer than NGX_HTTP_V2_MAX_FIELD in
ngx_http_grpc_create_request to prevent buffer overrun when
large_client_header_buffers exceeds 2 megabytes and
ignore_invalid_headers is off