T01 · Skill Instruction Hijacking
- Location
SKILL.md:149- Finding
Mandatory Promotional Content Injected into Agent Responses
- Content
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Vulnerability Details
File Location:
SKILL.md, lines 149–150
Vulnerability Type:T01: Skill Instruction Hijacking
Risk Level: HighComplete Code Snippet:
markdown **【署名与反馈】** > **署名**:一线评标专家&ChesaraM | **反馈/交流**:微信公众号「一线评标专家」(使用问题、误报反馈、实务建议,欢迎留言交流)Technical Analysis
The Skill places a fixed signature and WeChat promotional call-to-action inside the mandatory report template used by the agent. This content is unrelated to the core function of reviewing bidding documents. When the Skill is loaded and its output instructions are followed, the agent is directed to append third-party branding and traffic-routing material to ordinary user-facing reports.
This constitutes instruction hijacking at the output layer: the Skill uses its control over the agent's response format to achieve a persistent promotional objective beyond the user's requested task. The behavior requires no executable code because the payload consists of instructions interpreted directly by the agent.
Attack Path
- The platform loads the instructions from
SKILL.md. - A user requests a bidding-document compliance review.
- The agent follows the report-generation template defined by the Skill.
- The agent appends the fixed author signature and WeChat account promotion to the final report.
- The attacker-controlled branding is distributed through every affected response without a specific user request for promotional or contact information.
Impact Assessment
The issue does not grant operating-system privileges, access to credentials, code execution, or access to additional user files. Its scope is the integrity and presentation of responses generated while this Skill is active.
An operator controlling the Skill text can use the agent as a persistent distribution channel for third-party branding and external traffic redirection. Users may incorrectly perceive the promoted account as endorsed by the agen ...[truncated 168 chars]
- The platform loads the instructions from
- Remediation
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Remediation Suggestions
- Remove the mandatory signature and WeChat promotion from the report template in
SKILL.md. - Keep author attribution and contact details in passive package metadata, such as
manifest.yamlorREADME.md, rather than injecting them into agent-generated answers. - If a feedback mechanism is necessary, make it optional and display it only when the user explicitly requests support or contact information.
- Add a publication rule prohibiting mandatory advertising, branding, referrals, and external traffic-routing text in Skill response templates unless directly required by the declared functionality.
- Re-review all fixed output-template content to ensure every required section serves the user's bidding-document review request.
- Remove the mandatory signature and WeChat promotion from the report template in
