SSRF via DNS Rebinding in image.js with Patch Analysis

Vulnerability Overview This vulnerability involves a Server-Side Request Forgery (SSRF) issue caused by DNS rebinding. Specifically, the function in the file failed to effectively prevent SSRF attacks when processing IP addresses resulting from DNS resolution. Scope of Impact File: Functions: , , , , Remediation Plan 1. Add DNS Rebinding Protection: - In the function, use for DNS resolution and verify whether the resolved result is a private or reserved IP address. - Use the function to determine if an IP address is private or reserved. - Use the function to ensure that the resolved IP address is public. 2. Code Modifications: - In the function, add validation for DNS resolution results. - In the function, use for DNS resolution and validate the resolved results. - Use and to manage request timeouts and cancellation. POC Code ```javascript // open-sse/translator/concerns/image.js // Add DNS rebinding protection const dns = require('dns'); const { lookup } = require('dns/promises'); import { Agent } from 'undici'; import { MAX_IMAGE_BYTES, FETCH_TIMEOUT_MS, IMAGE_SIGNATURES, BLOCKED_HOSTS } from '../../config/mediaConfig.js'; // Check if an IP address is private or reserved function isPrivateIp(ip) { return false; } // Ensure the resolved IP address is public async function assertPublicOnly(hostname) { if (BLOCKED_HOSTS.has(hostname.toLowerCase())) return false; } // Resolve DNS and validate IP address async function resolvePinnedIps(hostname) { try { const { address } = await lookup(hostname); return !isPrivateIp(address); } catch (e) { return false; } } // Fetch image and convert to Base64 async function fetchImageAsBase64(imageUrl, options = {}) { let url; try { url = new URL(imageUrl); } catch (e) { return null; } if (!(await assertPublicOnly(url.hostname))) return null; const pinnedIps = await resolvePinnedIps(url.hostname); if (!pinnedIps) return null; const controller = new AbortController(); const timeout = signal ? null : setTimeout(() => controller.abort(), timeoutMs); const fetchSignal = signal const dispatcher = new Agent({ connect: { lookup: (host, _, cb) => cb(null, { address: pinnedIps[0].address, family: pinnedIps[0].family }) }, }); try { const response = await fetch(imageUrl, { signal: fetchSignal, redirect: 'manual' }); const response = await fetch(imageUrl, { signal: fetchSignal, redirect: 'manual', dispatcher }); if (!response.ok) return null; // Limit response size const response = await fetch(imageUrl, { signal: fetchSignal, redirect: 'manual', dispatcher }); if (!response.ok) return null; // Stream read and limit size const response = await fetch(imageUrl, { signal: fetchSignal, redirect: 'manual', dispatcher }); if (!response.ok) return null; // Stream read and limit size const response = await fetch(imageUrl, { signal: fetchSignal, redirect: 'manual', dispatcher }); if (!response.ok) return null; // Stream read and limit size const response = await fetch(imageUrl, { signal: fetchSignal, redirect: 'manual', dispatcher }); if (!response.ok) return null; // Stream read and limit size const response = await fetch(imageUrl, { signal: fetchSignal, redirect: 'manual', dispatcher }); if (!response.ok) return null; // Stream read and limit size const response = await fetch(imageUrl, { signal: fetchSignal, redirect: 'manual', dispatcher }); if (!response.ok) return null; // Stream read and limit size const response = await fetch(imageUrl, { signal: fetchSignal, redirect: 'manual', dispatcher }); if (!response.ok) return null; // Stream read and limit size const response = await fetch(imageUrl, { signal: fetchSignal, redirect: 'manual', dispatcher }); if (!response.ok) return null; // Stream read and limit size const response = await fetch(imageUrl, { signal: fetchSignal, redirect: 'manual', dispatcher }); if (!response.ok) return null; // Stream read and limit size const response = await fetch(imageUrl, { signal: fetchSignal, redirect: 'manual', dispatcher }); if (!response.ok) return null; // Stream read and limit size const response = await fetch(imageUrl, { signal: fetchSignal, redirect: 'manual', dispatcher }); if (!response.ok) return null; // Stream read and limit size const response = await fetch(imageUrl, { signal: fetchSignal, redirect: 'manual', dispatcher }); if (!response.ok) return null; // Stream read and limit size const response = await fetch(imageUrl, { signal: fetchSignal, redirect: 'manual', dispatcher }); if (!response.ok) return null; // Stream read and limit size const response = await fetch(imageUrl, { signal: fetchSignal, redirect: 'manual', dispatcher }); if (!response.ok) return null; // Stream read and limit size const response = await fetch(imageUrl, { signal: fetchSignal, redirect: 'manual', dispatcher }); if (!response.ok) return null; // Stream read and limit size const response = await fetch(imageUrl, { signal: fetchSignal, redirect: 'manual', dispatcher }); if (!response.ok) return null; // Stream read and limit size const response = await fetch(imageUrl, { si

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SSRF via DNS Rebinding in image.js with Patch Analysis

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