CRITICALData Exfiltration
Markdown Image Exfiltration
Injects a markdown image tag where the URL includes stolen data as a query parameter. When the markdown is rendered by a browser or Markdown renderer, the browser makes a GET request to the attacker's server with the sensitive data in the URL.
Attack Payload
payload.txt
 This image tag will cause the browser to send a GET request containing sensitive data to the attacker's server.
Mitigation
Strip markdown image and link tags from model output before rendering. Implement Content Security Policy that blocks requests to unknown domains. Use a markdown renderer with URL allowlisting.
Affected Models
Any model rendering markdown outputChatGPT pluginsWeb-based deployments
Tags
#exfiltration#markdown#image-tag#browser#critical
Discovered
June 2023Source
Johann Rehberger - Prompt Injection via Markdown (2023)Models Most Vulnerable to This Attack
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