[Security] API key exposed in request debug dumps via incomplete masking

[lynxlangya]

Security Issue: API key exposed in request debug dumps

Description

When an API request fails and triggers the debug dump mechanism (_dump_api_request_on_error), the resulting request_dump_*.json file contains the Authorization header with a partially masked API key:

"Authorization": "Bearer eyJhbGci...pdJk"

The masking function _mask_api_key_for_logs reveals the first 8 and last 4 characters of the key (key[:8]...key[-4:]), which significantly reduces entropy. For token-based auth (JWT/API keys), even partial key exposure is a security concern.

Additionally, the dump file contains:

• Full system prompt / instructions
• Complete message history
• All tool schemas (31 tools in our case)
• Error response details

Affected Code

run_agent.py, method _dump_api_request_on_error (around line 2677):

"headers": {
    "Authorization": f"Bearer {self._mask_api_key_for_logs(api_key)}",
    "Content-Type": "application/json",
},

Risk Assessment

• Current risk: Low to Medium — ~/.hermes/sessions/ directory is mode 700 (owner-only), so other local users cannot access the dumps.
• Potential risk escalation: If any future vulnerability allows directory traversal or if backups of ~/.hermes/ are made world-readable, the API key would be exposed with reduced entropy.
• Privacy risk: Full conversation history and system prompts in dumps are a privacy concern even without key exposure.

Recommended Fix

1. Remove Authorization header entirely from dump files — the URL is already recorded, so the presence of a request attempt is logged without exposing credentials:

   "headers": {
       "Content-Type": "application/json",
       # Authorization deliberately omitted from debug dumps
   },

2. Optionally: Consider also redacting or truncating the instructions (system prompt) and messages (conversation history) from the dump body, since these may contain sensitive context depending on the user's workflow.

3. Add a config flag redact_secrets_from_dumps: true (default true) to allow users who genuinely need to debug auth issues to temporarily disable redaction.

Environment

• hermes-agent: NousResearch/hermes-agent
• File: run_agent.py
• Function: _dump_api_request_on_error