ApostropheCMS: Host header controls server-side image fetch origin in @apostrophecms/ai-helper, enabling authenticated SSRF

影響: npm:@apostrophecms/ai-helper >= 1.0.0-beta.10, < 1.0.0-beta.13 → 1.0.0-beta.13

The @apostrophecms/ai-helper package builds the URL for a server-side image fetch by resolving a storage-relative path against req.baseUrl. When the site does not set a global base URL (the default), req.baseUrl is derived from the incoming HTTP Host header. An authenticated editor can generate a base64 AI image (which is persisted without a stored url) and then send an unauthorized PATCH accept request with an attacker-chosen Host header. The server then issues an outbound GET to the a…

Read on GitHub Advisory Database

On 10/21/2026, 03:11 AM, GitHub Advisory Database published "ApostropheCMS: Host header controls server-side image fetch origin in @apostrophecms/ai-helper, enabling authenticated SSRF" (type: Advisory). Severity is "Medium" (medium). Related technologies: JavaScript / Node.js. CVE: CVE-2026-113671.