Learning Paths
Indirect Prompt Injection
Follow external content from websites, email and documents into model context, then see how provenance, inspection, detection and authorization limit what that content can cause.
- Audience
- Developers integrating external content, security reviewers, red teamers
- Approximate time
- About 2 to 3 hours
- Prerequisites
- Foundations path or equivalent understanding of trust boundaries
Learning objectives
- Trace how external content becomes model-visible
- Compare website, email and document delivery channels
- Explain what provenance, inspection and detection can and cannot establish
- Read a real case with its evidence classification intact
Path sequence
01 Refresher and overview
02 Delivery channels
- 03 - AttackWebsite Prompt Injection
Web content as untrusted context for browsing and summarizing assistants.
- 04 - Lab - Controlled simulationWebsite Prompt Injection (Lab)
Apply the website trust path in a controlled simulation.
- 05 - AttackEmail Prompt Injection
Inbound email as attacker-reachable content in mailbox assistants.
- 06 - Lab - Controlled simulationEmail Prompt Injection (Lab)
Reason about sender, content and action scope in a controlled simulation.
- 07 - AttackDocument Prompt Injection
Shared and uploaded documents as a context source.
- 08 - Lab - Controlled simulationDocument / PDF Prompt Injection (Lab)
Separate extracted content from its trust level in a controlled simulation.
03 Defenses
- 09 - DefenseData Provenance
Tracks where content came from so later decisions can use origin as evidence.
- 10 - DefenseInput / Content Inspection
Inspection produces probabilistic evidence, not authorization.
- 11 - DefensePrompt Injection Detection
Detection findings are signals to act on, not proof of compromise or a permission decision.
Go deeper (optional)
- AttackSearch Result Prompt Injection
Search results as a ranked but untrusted source.
- AttackPDF Prompt Injection
PDF-specific extraction and rendering differences.
- AttackSource Code Prompt Injection
Repository content in coding assistants.
- ResearchNot What You've Signed Up For (Greshake et al.)
The paper that framed indirect prompt injection.
Knowledge check
Think through each question, then open it to compare with the expected reasoning. There is no score.
An email is from a known colleague. Does that make its text safe as model instructions?
No. Sender identity is provenance evidence, not authority to instruct the assistant. The content remains data for the task.
A detector flags instruction-like text in a document. What does that establish?
A signal worth preserving and acting on. It does not prove compromise, and a missed detection does not prove safety.
Why read EchoLeak as a disclosed vulnerability rather than a breach?
The record documents a reported and remediated issue with no known in-the-wild exploitation. Evidence classification should not be upgraded without evidence.
After this path, you should be able to...
- Trace an external source into model context
- Explain why source identity is not instruction authority
- Place provenance, inspection and detection correctly as evidence
- Describe a real case without overstating its evidence