T01 · Skill Instruction Hijacking
- Location
README.md:109- Finding
Skill Instructions Alter Agent Responses and Interrupt the Active Task
- Content
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Vulnerability Details
File Location:
README.md:109-118; related directives inreferences/auto-trigger.md:26-28,93-100andSKILL.md:41-43
Vulnerability Type: Agent instruction hijacking through automatic response modification and task blocking
Risk Level: MediumVulnerable Code Snippet
markdown ## Auto-Trigger When context reaches 70%, every answer includes:[🦅 Context: 72%] Compress recommended: /hawk-compress 148k → ~35k | Save 113k tokens
text At 85%+, forces confirmation before continuing.The related auto-trigger documentation further directs the agent to check context before responses, block nonessential output at high thresholds, require compression before continuing, replace the current conversation context after compression, and write a compression record to
memory/today.md.Technical Analysis
These are behavioral instructions intended to take effect merely because the skill is loaded. Rather than limiting activation to an explicit user request, the skill directs the agent to monitor every interaction, append skill-controlled content to ordinary responses, force confirmation, and eventually prevent the active task from continuing.
This behavior changes the goals and output policy of the current agent session. It can supersede unrelated user work by redirecting the conversation into the compression workflow. The package also does not contain the advertised
scripts/hawk-compressexecutable, so the forced workflow can block normal operation while directing the user toward a command that cannot successfully perform the documented function.The risk is instruction-level rather than operating-system privilege escalation. No evidence was found that these directives bypass platform-level system instructions, but they can interfere with lower-priority user tasks when the skill text is incorporated into agent context.
Attack Path
- A user or platform loads the sk ...[truncated 1237 chars]
- Remediation
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Remediation Suggestions
- Make compression strictly opt-in and activate it only after an explicit user command.
- Remove instructions requiring context checks before every response.
- Remove mandatory notices that alter all unrelated agent responses.
- Remove language directing the agent to refuse, block, or delay the active task.
- Treat context thresholds as advisory telemetry rather than authorization to change session behavior.
- Require explicit user approval before replacing conversation context or writing any compression history.
- State that system instructions, active user requests, and platform safety requirements always take precedence over the skill workflow.
- Add the documented
scripts/hawk-compressexecutable or remove installation and invocation instructions that reference it. - Add tests confirming that loading the skill alone does not modify responses, write persistent state, or interrupt unrelated tasks.