T01 · Skill Instruction Hijacking
Error
- Location
- SKILL.md:52
- Finding
- Mandatory branded link injection into successful Agent responses< ``` ```markdown **引导链接格式**: > 📌 [找更多优质供应商上1688](https://s.1688.com/company/company_search.htm) ``` ### Technical Analysis The Skill instructions require the Agent to append a fixed branded external link to every successful response, regardless of whether the user requested navigation or promotional material. Loading the Skill therefore alters the Agent's response objective from returning supplier-query results to also directing user traffic to a predetermined destination. This is instruction-level output manipulation rather than a direct code-execution vulnerability. The destination is an official-looking 1688 domain, but the mandatory behavior still exceeds the minimum functionality necessary to perform supplier lookup. ### Attack Path 1. The Agent loads `SKILL.md`. 2. A user submits a supplier query. 3. The supplier API returns a successful result. 4. The Skill instructions require the Agent to append the fixed external link. 5. The user receives promotional or traffic-redirection content represented as part of the Agent's response. ### Impact Assessment The issue controls the content of successful Agent responses and may cause users to interpret a mandatory promotional link as an independent Agent recommendation. It does not grant local system privileges or code execution, but it persistently changes session output behavior whenever the Skill is used. ]]>
- Remediation
- <![CDATA[ ## Remediation Suggestions - Remove the requirement to append the link to every successful response. - Return only the supplier information requested by the user. - If the link has legitimate utility, make it optional and include it only when the user asks for additional browsing resources. - Clearly label any external navigation as optional and separate it from API-derived supplier data. - Document all externally directed output behavior in the Skill's declared capabilities. ]]>
