Research demo
Unseeable prompt injections in screenshots: Comet OCR injection and Fellou navigation injection
AIR-2025-0152 AIR record · 2025-10-brave-unseeable-screenshot-injection
From the supporting source
Agentic browser assistants can be prompt-injected by untrusted webpage content, rendering protections such as the same-origin policy irrelevant because the assistant executes with the user's authenticated privileges.brave.com
The record
Disclosed
2025-10-21
Vendor
Perplexity; Fellou; Opera
Product
Perplexity Comet; Fellou; Opera Neon
Risk domain
Privacy › Data exfiltration channels
Also touches
Unsafe actuation
System type
Generative model
Who acted
Agent acted — the agents acted on OCR'd screenshot injections
Attack surface
Browser agent
Autonomy level
Semi-autonomous
Initial vector
Screenshot ocr injection
Impact type
Data exfiltration, Unauthorized actions
Confidence
High
Submitted by
EAI Internal
Crosswalk
- OWASP Agentic Top 10 (2026)
- ASI02 – Tool Misuse and Exploitation
- MITRE ATLAS
- AML.T0024 – Exfiltration via AI Inference API
- NIST AI RMF
- MAP 4.2
- EU AI Act
- Article 10
- ISO/IEC
- TR 24028; 23894
- AIUC-1
- A. Data & Privacy
- Scope
- tool misuse
- Mitigation
- Monitor network traffic for anomalous patterns; Restrict egress destinations.
- Taxonomy
- Enkrypt AI agent risk taxonomy · Black-Box Red Teaming of Agentic AI: A Taxonomy-Driven Framework for Automated Risk Discovery
Blast radius
users of the affected agentic browsers who screenshot or navigate to attacker pages
Capability abused
Defense & remediation
Recorded defense
vendor content filters; user-visible action logs
Guardrail kinds
Unknown
Guardrail outcome
Silent
Fix shipped
partial; Opera Neon details released 2025-10-31 after coordination
Taxonomy & references
Curator notes
Two distinct techniques: (1) Comet - faint light-blue text on yellow background invisible to humans but recovered by OCR when the user screenshots the page; (2) Fellou - merely asking the browser to navigate to an attacker URL sends page text to the LLM where it overrides user intent. A fourth affected browser was withheld. Brave's stated conclusion: agentic browsing is inherently dangerous today.
Supporting sources
Cite as
Enkrypt AI. "Unseeable prompt injections in screenshots: Comet OCR injection and Fellou navigation injection". AIR, AIR-2025-0152. https://agentincident.vercel.app/i/AIR-2025-0152/ (accessed 2026-10-19).