Fides is an open-source privacy engineering platform. Starting in version 2.19.0 and prior to version 2.44.0, the Email Templating feature uses Jinja2 without proper input sanitization or rendering environment restrictions, allowing for Server-Side Template Injection that grants Remote Code Execution to privileged users. A privileged user refers to an Admin UI user with the default Owner or Contributor role, who can escalate their access and execute code on the underlying Fides Webserver container where the Jinja template rendering function is executed. The vulnerability has been patched in Fides version 2.44.0. Users are advised to upgrade to this version or later to secure their systems against this threat. There are no workarounds.
The product uses a template engine to insert or process externally-influenced input, but it does not neutralize or incorrectly neutralizes special elements or syntax that can be interpreted as template expressions or other code directives when processed by the engine.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Fides | Ethyca | 2.19.0 (including) | 2.44.0 (excluding) |
Many web applications use template engines that allow developers to insert externally-influenced values into free text or messages in order to generate a full web page, document, message, etc. Such engines include Twig, Jinja2, Pug, Java Server Pages, FreeMarker, Velocity, ColdFusion, Smarty, and many others - including PHP itself. Some CMS (Content Management Systems) also use templates. Template engines often have their own custom command or expression language. If an attacker can influence input into a template before it is processed, then the attacker can invoke arbitrary expressions, i.e. perform injection attacks. For example, in some template languages, an attacker could inject the expression “{{7*7}}” and determine if the output returns “49” instead. The syntax varies depending on the language. In some cases, XSS-style attacks can work, which can obscure the root cause if the developer does not closely investigate the root cause of the error. Template engines can be used on the server or client, so both “sides” could be affected by injection. The mechanisms of attack or the affected technologies might be different, but the mistake is fundamentally the same.