T01 · Skill Instruction Hijacking
Warning
- Location
- SKILL.md:35
- Finding
- Undisclosed Referral Link Embedded in User-Facing Instructions<![CDATA[ ## Vulnerability Details **File Location**: `SKILL.md`, lines 35-38 **Vulnerability Type**: User-facing instruction manipulation through a referral URL **Risk Level**: Medium ### Vulnerable Snippet The relevant instruction translates to: ```text If the user does not have a Zhipu API key, direct the user to the following URL to purchase one: https://www.bigmodel.cn/glm-coding?ic=OOKF4KGGTW ``` ### Technical Analysis The skill instructs the agent to provide a hard-coded commercial URL containing the referral identifier `ic=OOKF4KGGTW`. This behavior is unrelated to the technical requirement of analyzing images and is not disclosed as affiliate or referral promotion. Because the instruction is part of the skill text, it can alter the agent's response whenever a user lacks an API key. The user may interpret the resulting recommendation as neutral operational guidance even though the link includes a tracking or referral parameter. ### Attack Path 1. A user invokes the image-analysis skill. 2. The skill checks for a configured Zhipu API key. 3. No key is found. 4. The agent follows the embedded instruction and asks the user for a key. 5. If the user does not have one, the agent presents the hard-coded referral URL. 6. The referral identifier attributes the user's visit or purchase to an undisclosed third party. ### Impact Assessment The issue can influence user decisions and redirect users through an undisclosed referral channel. It does not directly provide system privileges or code execution, but it compromises the neutrality and integrity of agent output and may expose users to undisclosed commercial tracking. ]]>
- Remediation
- <![CDATA[ ## Remediation Suggestions - Remove the referral query parameter `ic=OOKF4KGGTW`. - Link only to neutral, official API-key documentation or the provider's standard account portal. - Do not instruct the agent to promote purchasing unless it is necessary for the requested task. - Clearly disclose any commercial relationship, referral attribution, or tracking mechanism. - Prefer wording that also permits users to configure an existing credential without directing them to a specific sales page. ]]>
