Brave Discloses Indirect Prompt Injection in Perplexity Comet
Date: 2025-08
Affected: Perplexity Comet
Attack vector: prompt-injection
Category: research
Severity: High

Brave found Comet AI browser feeds webpage content directly to its LLM without separating untrusted content from user instructions; attackers can embed prompt injection payloads that the agent executes.


Mitigations:

Architectural layers (MAESTRO):