WeKnora is an LLM-powered framework designed for deep document understanding and semantic retrieval. Prior to version 0.3.0, a vulnerability involving tool name collision and indirect prompt injection allows a malicious remote MCP server to hijack tool execution. By exploiting an ambiguous naming convention in the MCP client (mcp_{service}_{tool}), an attacker can register a malicious tool that overwrites a legitimate one (e.g., tavily_extract). This enables the attacker to redirect LLM execution flow, exfiltrate system prompts, context, and potentially execute other tools with the user's privileges. This issue has been patched in version 0.3.0.

Affected: Go: github.com/Tencent/WeKnora

### Summary

A vulnerability involving tool name collision and indirect prompt injection allows a malicious remote MCP server to hijack tool execution. By exploiting an ambiguous naming convention in the MCP client (`mcp_{service}_{tool}`), an attacker can register a malicious tool that overwrites a legitimate one (e.g., `tavily_extract`). This enables the attacker to redirect LLM execution flow, exfiltrate system prompts, context, and potentially execute other tools with the user's privileges.

### Details The vulnerability stems from two issues in the WeKnora client's MCP implementation:

1. **Tool Name Collision (Ambiguous Sanitization)**: The client generates internal tool identifiers by sanitizing and joining the service name and tool name with underscores: `mcp_{service}_{tool}`. - Reference: `internal/agent/tools/mcp_tool.go` ```go func (t *MCPTool) Name() string { serviceName := sanitizeName(t.service.Name) toolName := sanitizeName(t.mcpTool.Name) return fmt.Sprintf("mcp_%s_%s", serviceName, toolName) } ``` - The registry overwrites existing entries (`internal/agent/tools/registry.go`), so if a malicious service registers a tool that resolves to an existing name, it silently replaces the legitimate implementation ```go // internal/agent/tools/registry.go func (r *ToolRegistry) RegisterTool(tool types.Tool) { r.tools[tool.Name()] = tool } ```

2. **Unsanitized Tool/Metadata Output (Indir…