AI agents call extract_fields to retrieve information from Wireshark MCP without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool retrieves and queries packet data fields from network traffic captures—a read operation with no capability to modify, delete, or execute code. However, severity is high rather than low because extracted packet data can include sensitive information (credentials, API keys, personally identifiable information, application payloads) that could be exposed if an AI agent misuses this tool to extract and…
From the tool's definition Tool name 'extract_fields' with description '提取特定字段信息' (extract specific field information). Context indicates this is part of Wireshark packet analysis suite. The tool extracts data from network packets captured in PCAP files or live captures.
Documented attack patterns abuse exactly the kind of access extract_fields gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Wireshark MCP, and nothing reaches the server without passing your rules. This is the rule we recommend for extract_fields:
{
"version": "1",
"default": "deny",
"tools": {
"extract_fields": {}
}
}extract_fields is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
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提取特定字段信息. It is categorised as a Read tool in the Wireshark MCP MCP Server, which means it retrieves data without modifying state.
Register the Wireshark MCP server in PolicyLayer and add a rule for extract_fields: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Wireshark MCP. Nothing to install.
extract_fields is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the extract_fields rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for extract_fields. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
extract_fields is provided by the Wireshark MCP server (jayimu/wireshark_mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Wireshark MCP, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
10 Wireshark MCP tools catalogued and risk-classified — across an index of 43,000+ MCP servers.