Office Open Xml |work| Download 【DELUXE · 2025】

XmlReaderSettings settings = new XmlReaderSettings(); settings.DtdProcessing = DtdProcessing.Prohibit; settings.XmlResolver = null; A malicious .docx upload (if your system re-uploads user files) may contain a document.xml compressed from 1 KB to 1 GB inflated. When your server processes it for download generation, memory is exhausted.

<!DOCTYPE doc [ <!ENTITY xxe SYSTEM "file:///etc/passwd"> ]> <w:p><w:r><w:t>&xxe;</w:t></w:r></w:p> Always disable external entities and DTDs in your XML parser. office open xml download

When reading any ZIP part, normalize the entry name and reject any containing .. or absolute paths. 5. Reference Implementation: A Secure Streaming Downloader We present a pseudo-code implementation for a REST endpoint that generates a simple .docx report from JSON data, using streaming and security best practices. 5.1 System Architecture [JSON Input] -> [Streaming XML Writer] -> [In-memory ZIP stream] -> [HTTP Response] ^ | | (direct write) v [Content Types & Relationships] [File Download] 5.2 Core Implementation (C#/.NET Core Example) [HttpGet("report.docx")] public IActionResult GenerateDocx(string title, string content) When reading any ZIP part, normalize the entry

Office Open XML, OOXML, Document Generation, File Download, XML Security, ZIP Compression, REST API. 1. Introduction In enterprise web applications, generating downloadable office documents from structured data (e.g., invoices, reports, spreadsheets) is a ubiquitous requirement. Prior to OOXML, server-side generation often relied on binary formats ( .doc , .xls ) via COM interop (unreliable and non-scalable) or HTML-to-PDF converters (loss of semantic fidelity). The introduction of OOXML solved this by providing an open, royalty-free, XML-based standard. // Title paragraph xmlWriter.WriteStartElement("w:p")

| Method | Peak Memory (MB) | Time (s) | Max Concurrent Requests | | :--- | :--- | :--- | :--- | | (deprecated) | 1,200 | 62 | 2 (serialized) | | Open XML SDK + DOM | 890 | 28 | 8 | | Open XML SDK + Streaming (our method) | 230 | 22 | 35 |

– Write XML directly to the ZIP entry's output stream using a XmlWriter (or equivalent) without retaining the entire tree.

// 3. Main document part - STREAMING XML (no DOM) var docEntry = archive.CreateEntry("word/document.xml"); using (var docStream = docEntry.Open()) using (var xmlWriter = XmlWriter.Create(docStream, new XmlWriterSettings Indent = true )) xmlWriter.WriteStartDocument(); xmlWriter.WriteStartElement("w:document", "http://schemas.openxmlformats.org/wordprocessingml/2006/main"); xmlWriter.WriteStartElement("w:body"); // Title paragraph xmlWriter.WriteStartElement("w:p"); xmlWriter.WriteStartElement("w:r"); xmlWriter.WriteStartElement("w:t"); xmlWriter.WriteString(title); xmlWriter.WriteEndElement(); // t xmlWriter.WriteEndElement(); // r xmlWriter.WriteEndElement(); // p // Content paragraph (sanitized) var safeContent = System.Security.SecurityElement.Escape(content); xmlWriter.WriteStartElement("w:p"); xmlWriter.WriteStartElement("w:r"); xmlWriter.WriteStartElement("w:t"); xmlWriter.WriteString(safeContent); xmlWriter.WriteEndElement(); xmlWriter.WriteEndElement(); xmlWriter.WriteEndElement(); xmlWriter.WriteEndElement(); // body xmlWriter.WriteEndElement(); // document xmlWriter.WriteEndDocument();