The CVSS 7.7 score for this vulnerability misrepresents the actual risk because it assumes an 'authenticated attacker' represents a meaningful security boundary. In this case, the attacker doesn't need credentials at all — they need only to influence an AI agent that already holds those credentials. This is an induced-attack surface, and it fundamentally changes the threat model.
The vulnerable function confluence_upload_attachment accepts a file path and returns file contents. The path traversal itself is the immediate bug, but the severity compounds through the credential exfiltration path: the tool can read CONFLUENCE_API_TOKEN from the server's environment, pivoting from file disclosure to full account compromise in a single call. The token then grants access to every downstream system that integration touches — Confluence spaces, Jira instances, webhooks.
The patch adds validate_safe_path, which addresses the symptom but not the underlying design failure. This tool was built for AI agents but secured as if it served human users. When a human provides a file path, they're constrained by what they can type. When an AI agent provides a file path, it's constrained only by what an attacker embedded in the content the agent was processing. That's a fundamentally different threat model, yet the codebase appears to have treated path validation as a copy-paste feature rather than a context-dependent security boundary.
What you should do: audit every MCP tool in your deployment that accepts file paths, URLs, JQL queries, or similar inputs from client code. The issue isn't just this function — it's the pattern of trusting client-provided paths in agentic contexts where the client is a language model processing untrusted content. Ask whether each tool's input validation accounts for the fact that the 'client' might be executing attacker-controlled instructions rather than a known human operator. If validate_safe_path uses a blacklist approach, test it against path obfuscation techniques including double encoding, null bytes, and Unicode normalization.
The real exposure isn't the path traversal itself — it's that your AI agent infrastructure may be processing attacker-controlled content and calling privileged tools on that content's behalf. The CVSS score measures a direct exploit; this is an indirect one, and the scoring framework has no vocabulary for it.