Description

Detects XML External Entity (XXE) vulnerabilities by identifying XML parsers configured with NOENT=true, which allows processing of external entities. This dangerous configuration can lead to XXE attacks including file disclosure, server-side request forgery, and denial of service.

Detection Strategy

• Check XML parser configuration settings and initialization code

• Flag instances where NOENT or similar entity processing options are set to true

• Report vulnerability when XML parser is configured to process external entities

Vulnerable code example

const libxmljs = require('libxmljs');
const fs = require('fs');

function parseXml() {
  const xml = fs.readFileSync('input.xml', 'utf8');
  
  // Vulnerable: enables external entity processing (XXE)
  const xmlDoc = libxmljs.parseXmlString(xml, {...

✅ Secure code example

const libxmljs = require('libxmljs');
const fs = require('fs');

function parseXml() {
  const xml = fs.readFileSync('input.xml', 'utf8');
  
  // Safe: noent defaults to false, preventing XXE attacks
  const xmlDoc = libxmljs.parseXmlString(xml);...