GHSA-j4f3-55x4-r6q2: praisonai: MCP HTTP server unauthenticated tool invocation

GHSA-j4f3-55x4-r6q2 CRITICAL
Published June 18, 2026
CISO Take

The praisonai npm TypeScript MCPServer (versions 1.5.0–1.7.1) exposes all MCP methods — tools/call, resources/read, and prompts/get — over HTTP with zero authentication and binds to all network interfaces by default (::), meaning any host that can reach the port gets full unauthenticated tool access. With a CVSS of 9.8 and a trivial exploit path (a plain HTTP POST with no credentials), this is one of the highest-severity AI agent vulnerabilities published to date; the package even ships an MCPSecurity class that is never wired into the HTTP transport, making the omission a clear implementation gap rather than a design trade-off. Real blast radius depends on which tools the application registers, but MCP tools routinely wrap filesystem ops, database queries, code execution, email/Slack actions, and API calls — all running with the server process's credentials. Upgrade to praisonai >= 1.7.2 immediately; if patching is not possible, block the MCP port at the firewall or place an authenticated reverse proxy in front of it.

Sources: GitHub Advisory ATLAS CVSS

What is the risk?

Critical risk. CVSS 9.8 with AV:N/AC:L/PR:N/UI:N reflects real-world exploitability: the attack is a single unauthenticated HTTP POST, requires no prior knowledge of the environment, and ignores invalid credentials. The default bind to :: (all interfaces) widens exposure beyond localhost. AI agent deployments are especially high-risk because registered MCP tools are commonly privileged — code execution, file system access, external API calls — meaning exploitation is trivially escalated to full server compromise depending on tool registration. The MCPSecurity class existing but being unused creates a false sense of security for developers who may assume it is active.

How does the attack unfold?

Network Discovery
Attacker scans for open HTTP ports on AI agent servers and identifies a running praisonai MCPServer bound to all interfaces (::) on the configured port.
AML.T0006
Tool Enumeration
Attacker sends an unauthenticated JSON-RPC POST with method tools/list and receives a complete inventory of registered MCP tool names, descriptions, and input schemas.
AML.T0084.001
Unauthenticated Tool Invocation
Attacker selects a high-impact tool (e.g., shell exec, file read, API caller) and invokes it via tools/call with crafted arguments — the server executes the handler with no credential check.
AML.T0053
Impact / Lateral Movement
Depending on registered tools, attacker achieves code execution, credential theft, data exfiltration, or destructive actions running as the server process with its full privileges and secrets.
AML.T0086

What systems are affected?

Package Ecosystem Vulnerable Range Patched
PraisonAI npm >= 1.5.0, <= 1.7.1 1.7.2
1 dependents 89% patched ~0d to patch Full package profile →

Do you use PraisonAI? You're affected.

How severe is it?

CVSS 3.1
9.8 / 10
EPSS
N/A
Exploitation Status
No known exploitation
Sophistication
Trivial

What is the attack surface?

AV AC PR UI S C I A
AV Network
AC Low
PR None
UI None
S Unchanged
C High
I High
A High

What should I do?

6 steps
  1. PATCH

    Upgrade praisonai npm to >= 1.7.2 immediately. Verify the fix wires MCPSecurity into the HTTP transport and binds to 127.0.0.1 by default.

  2. FIREWALL (if patching is delayed): Block the MCP HTTP port (default 3000) at the host firewall or cloud security group, restricting access to trusted IPs only.

  3. STDIO transport: Switch MCPServer to stdio transport (set stdio: true in config) as a temporary mitigation; stdio does not expose an HTTP listener.

  4. REVERSE PROXY

    If HTTP transport is required, place an authenticated reverse proxy (nginx, Caddy with basicauth) in front of the MCP port before deploying.

  5. DETECT

    Audit access logs for unexpected POST requests to /mcp or JSON-RPC endpoints with tools/list, tools/call, resources/read, or prompts/get method fields — unauthenticated calls are the indicator of compromise.

  6. AUDIT TOOLS

    Inventory all MCP tools registered in deployed servers to understand the blast radius in your environment.

How is it classified?

Which compliance frameworks are affected?

This CVE is relevant to:

EU AI Act
Article 15 - Accuracy, robustness and cybersecurity Article 9 - Risk management system
ISO 42001
A.6.2.4 - Access control for AI systems A.8.4 - AI system security
NIST AI RMF
GOVERN 1.1 - Organizational practices for AI risk MANAGE 2.2 - Risk responses — treatment of identified risks
OWASP LLM Top 10
LLM08:2025 - Excessive Agency

Frequently Asked Questions

What is GHSA-j4f3-55x4-r6q2?

The praisonai npm TypeScript MCPServer (versions 1.5.0–1.7.1) exposes all MCP methods — tools/call, resources/read, and prompts/get — over HTTP with zero authentication and binds to all network interfaces by default (::), meaning any host that can reach the port gets full unauthenticated tool access. With a CVSS of 9.8 and a trivial exploit path (a plain HTTP POST with no credentials), this is one of the highest-severity AI agent vulnerabilities published to date; the package even ships an MCPSecurity class that is never wired into the HTTP transport, making the omission a clear implementation gap rather than a design trade-off. Real blast radius depends on which tools the application registers, but MCP tools routinely wrap filesystem ops, database queries, code execution, email/Slack actions, and API calls — all running with the server process's credentials. Upgrade to praisonai >= 1.7.2 immediately; if patching is not possible, block the MCP port at the firewall or place an authenticated reverse proxy in front of it.

Is GHSA-j4f3-55x4-r6q2 actively exploited?

No confirmed active exploitation of GHSA-j4f3-55x4-r6q2 has been reported, but organizations should still patch proactively.

How to fix GHSA-j4f3-55x4-r6q2?

1. PATCH: Upgrade praisonai npm to >= 1.7.2 immediately. Verify the fix wires MCPSecurity into the HTTP transport and binds to 127.0.0.1 by default. 2. FIREWALL (if patching is delayed): Block the MCP HTTP port (default 3000) at the host firewall or cloud security group, restricting access to trusted IPs only. 3. STDIO transport: Switch MCPServer to stdio transport (set stdio: true in config) as a temporary mitigation; stdio does not expose an HTTP listener. 4. REVERSE PROXY: If HTTP transport is required, place an authenticated reverse proxy (nginx, Caddy with basicauth) in front of the MCP port before deploying. 5. DETECT: Audit access logs for unexpected POST requests to /mcp or JSON-RPC endpoints with tools/list, tools/call, resources/read, or prompts/get method fields — unauthenticated calls are the indicator of compromise. 6. AUDIT TOOLS: Inventory all MCP tools registered in deployed servers to understand the blast radius in your environment.

What systems are affected by GHSA-j4f3-55x4-r6q2?

This vulnerability affects the following AI/ML architecture patterns: AI agent frameworks (MCP-based), Agentic pipelines with tool use, Model serving with tool integration, Multi-agent orchestration systems, LLM application backends with HTTP transport.

What is the CVSS score for GHSA-j4f3-55x4-r6q2?

GHSA-j4f3-55x4-r6q2 has a CVSS v3.1 base score of 9.8 (CRITICAL).

What is the AI security impact?

Affected AI Architectures

AI agent frameworks (MCP-based)Agentic pipelines with tool useModel serving with tool integrationMulti-agent orchestration systemsLLM application backends with HTTP transport

MITRE ATLAS Techniques

AML.T0006 Active Scanning
AML.T0049 Exploit Public-Facing Application
AML.T0053 AI Agent Tool Invocation
AML.T0084.001 Tool Definitions
AML.T0085.001 AI Agent Tools
AML.T0086 Exfiltration via AI Agent Tool Invocation

Compliance Controls Affected

EU AI Act: Article 15, Article 9
ISO 42001: A.6.2.4, A.8.4
NIST AI RMF: GOVERN 1.1, MANAGE 2.2
OWASP LLM Top 10: LLM08:2025

What are the technical details?

Original Advisory

## Summary The published npm package `praisonai` exports a TypeScript `MCPServer` that can expose tools, resources, and prompts over an HTTP JSON-RPC transport with: ```ts await server.start({ port: 3000 }); ``` The HTTP transport has no authentication or authorization path. `MCPServerConfig` does not expose an auth/security setting, `startHttp()` ignores the `Authorization` header, and every POST request is parsed and forwarded directly to `handleRequest()`. That request handler dispatches sensitive MCP methods such as `tools/call`, `resources/read`, and `prompts/get`. The implementation also calls `this.httpServer.listen(port)` without a host argument. In Node.js this binds to the unspecified address; the local PoV observed `{ address: "::", family: "IPv6" }`, making the service reachable on all interfaces on systems where the port is exposed. This lets any network client that can reach the HTTP port list tools and invoke registered server-side tools without credentials. Supplying `Authorization: Bearer invalid` makes no difference. ## Technical Details `MCPServerConfig` exposes server metadata, tools/resources/prompts, stdio, port, and logging. It does not expose an auth token, authorization policy, `MCPSecurity` instance, authorization callback, or loopback-only option: ```text src/praisonai-ts/src/mcp/server.ts 57: export interface MCPServerConfig { 63: tools?: MCPServerTool[]; 65: resources?: MCPResource[]; 67: prompts?: MCPPrompt[]; 69: stdio?: boolean; 73: port?: number | null; 75: logging?: boolean; ``` `handleRequest()` dispatches sensitive MCP methods directly: ```text src/praisonai-ts/src/mcp/server.ts 203: async handleRequest(request: MCPRequest): Promise<MCPResponse> { 219: case 'tools/call': 220: result = await this.handleToolCall(params); 225: case 'resources/read': 226: result = await this.handleResourceRead(params); 231: case 'prompts/get': 232: result = await this.handlePromptGet(params); ``` The tool dispatcher invokes the registered handler: ```text src/praisonai-ts/src/mcp/server.ts 285: private async handleToolCall(params?: any): Promise<any> { 288: const tool = this.tools.get(name); 298: const result = await tool.handler(args ?? {}); ``` The HTTP server parses every POST body and forwards it to `handleRequest()` with no authentication check: ```text src/praisonai-ts/src/mcp/server.ts 403: async startHttp(port: number): Promise<void> { 409: this.httpServer = http.createServer(async (req, res) => { 416: const response = await this.handleRequest(request); 434: this.httpServer.listen(port, () => { ``` This is a guard-coverage gap because the same TypeScript package already ships a dedicated MCP security manager: ```text src/praisonai-ts/src/mcp/security.ts 2: * MCP Security - Authentication, authorization, and rate limiting 79: export class MCPSecurity { 132: async check(request: { path?: string; method?: string; headers?: ... }) 167: const auth = headers['authorization'] ?? headers['Authorization']; 239: case 'authenticate': 303: export function createApiKeyPolicy(...) ``` `MCPServer` never references that security manager in its HTTP request path. ### Why This Is Not Intended Behavior PraisonAI's MCP documentation says MCP servers allow AI models to use tools and communicate with external systems. The same page's security considerations say to use API keys in production, implement rate limiting, validate incoming requests, use HTTPS, and limit custom tool permissions. PraisonAI's security page also documents prior breaking hardening where API servers were changed to require authentication by default and bind to `127.0.0.1` instead of `0.0.0.0`. It separately lists MCP `tools/call` issues as security vulnerabilities. The npm TypeScript `MCPServer` does the opposite: - `start({ port })` binds to the unspecified address; - `MCPServerConfig` has no auth/security field; - `startHttp()` does not inspect `Authorization`; - `tools/list`, `tools/call`, `resources/read`, and `prompts/get` all dispatch without authentication; and - `MCPSecurity` exists but is not wired into the HTTP server. This is not merely a deployment hardening suggestion. The package exposes an HTTP MCP server API and a separate security manager, but the server's own HTTP transport provides no way to enforce the documented API-key requirement. ## PoV The PoV installs the published npm package in a temporary project, starts the exported `MCPServer` on a local ephemeral port, and sends loopback JSON-RPC requests. It does not call any LLM provider or external service after package installation. Run from a local reproduction checkout: ```fish node poc/pov_poc.js 1.7.1 ``` Observed result: ```json { "package": "praisonai", "version": "1.7.1", "mcpServerExported": true, "bindAddress": { "address": "::", "family": "IPv6" }, "initialize": { "status": 200 }, "list": { "status": 200, "json": { "result": { "tools": [ { "name": "admin_reset_marker", "description": "privileged marker tool" } ] } } }, "callNoAuth": { "status": 200, "json": { "result": { "content": [ { "text": "invoked:NO_AUTH_MARKER" } ] } } }, "callBadAuth": { "status": 200, "json": { "result": { "content": [ { "text": "invoked:BAD_AUTH_MARKER" } ] } } }, "calls": [ "NO_AUTH_MARKER", "BAD_AUTH_MARKER" ], "patchedControl": { "noAuthStatus": 401, "withAuthStatus": 200, "patchedCalls": [ "called" ] } } ``` Interpretation: - unauthenticated `initialize` returns `200`; - unauthenticated `tools/list` returns the registered tool; - unauthenticated `tools/call` invokes the registered tool; - invalid `Authorization: Bearer invalid` is ignored and also invokes the tool; - the server binds to the unspecified IPv6 address; and - a minimal local wrapper that enforces a bearer token blocks the same no-auth call with `401`, demonstrating that the PoV is exercising the missing authentication boundary. ## PoC The PoV section above contains the local reproduction command, input, and decisive output. ## Impact Any client that can reach the npm TypeScript `MCPServer` HTTP port can list and invoke all registered MCP tools without credentials. Real impact depends on which tools, resources, and prompts the application registers. MCP tools commonly wrap filesystem operations, API clients, database queries, agent actions, deployment operations, email/Slack actions, browser automation, and code execution. Because those handlers run with the server process privileges and server-side credentials, an unauthenticated caller can drive the same actions. `resources/read` and `prompts/get` are also unauthenticated and may disclose application data or prompt material registered by the server. ### Severity Suggested severity: Critical. Rationale: - `AV`: exploitation is a direct HTTP JSON-RPC request. - `AC`: no race, user gesture, or special state is required. - `PR`: no credentials are required; invalid credentials are ignored. - `UI`: no user interaction is required after the server is running. - `S`: impact is within the authority of the MCP server process and its registered tools. - `C`: resources, prompts, and tool-returned data may expose sensitive data. - `I`: unauthenticated callers can drive server-side tools. - `A`: unauthenticated callers can invoke destructive or resource-consuming tools if registered. ## Suggested Fix Recommended minimum fix: 1. Add `security`, `auth`, `authRequired`, `apiKeys`, or `authorize(req)` to `MCPServerConfig`. 2. Fail closed for HTTP transport when auth is not configured, unless the caller explicitly opts into unauthenticated loopback-only development mode. 3. Bind HTTP transport to `127.0.0.1` by default, or require an explicit host when binding to all interfaces. 4. Call `MCPSecurity.check(...)` or equivalent middleware before every non-health POST request reaches `handleRequest()`. 5. Return `401` for missing or invalid credentials before dispatching `initialize`, `tools/list`, `tools/call`, `resources/read`, or `prompts/get`. 6. Add Origin/Host protections for loopback HTTP transports to reduce DNS rebinding exposure. 7. Add regression tests proving: - no-auth `tools/list` returns `401`; - no-auth `tools/call` returns `401` and does not invoke the handler; - invalid bearer token returns `401`; - valid bearer token invokes the handler; - default `start({ port })` does not bind to all interfaces without an explicit opt-in. ## Affected Package/Versions - Repository: `MervinPraison/PraisonAI` - Ecosystem: `npm` - Package: `praisonai` - Component: `src/praisonai-ts/src/mcp/server.ts` - Related unused security component: `src/praisonai-ts/src/mcp/security.ts` - Current npm version checked: `1.7.1` - Refreshed `origin/main` checked: `1ad58ca02975ff1398efeda694ea2ab78f20cf3e` Confirmed affected range: ```text >= 1.5.0, <= 1.7.1 ``` Boundary: ```text 1.4.0 does not export MCPServer and does not ship dist/mcp/server.js. ``` No fixed npm version is known at the time of this report. ### Version Sweep The included sweep installs selected npm versions and checks the HTTP `MCPServer` path: ```fish node poc/version_sweep_poc.js ``` Observed result: ```text 1.4.0: mcpServerExported=false, hasDistMcpServer=false 1.5.0: mcpServerExported=true, hasDistMcpServer=true, noAuthToolCallInvoked=true, bindAddress=:: 1.5.4: mcpServerExported=true, hasDistMcpServer=true, noAuthToolCallInvoked=true, bindAddress=:: 1.6.0: mcpServerExported=true, hasDistMcpServer=true, noAuthToolCallInvoked=true, bindAddress=:: 1.7.0: mcpServerExported=true, hasDistMcpServer=true, noAuthToolCallInvoked=true, bindAddress=:: 1.7.1: mcpServerExported=true, hasDistMcpServer=true, noAuthToolCallInvoked=true, bindAddress=:: ``` ## Advisory History Known related public advisories: - `GHSA-9mqq-jqxf-grvw` / `CVE-2026-44336`: `pip:praisonai` MCP `tools/call` path traversal to RCE in Python `praisonai mcp serve`, affected `<= 4.6.33`. - `CVE-2026-47394`: `pip:praisonai` incomplete MCP path traversal fix affecting Python workflow/deploy handlers. - poc: deprecated Python MCP SSE Host/Origin/session issue. - poc: npm TypeScript AgentOS missing authentication. This report is distinct because it targets: - ecosystem: `npm`; - package: `praisonai`; - component: `src/praisonai-ts/src/mcp/server.ts`; - root cause: TypeScript `MCPServer` HTTP transport missing auth and not using `MCPSecurity`; - primitive: unauthenticated and invalid-auth JSON-RPC `tools/call` invokes arbitrary registered TypeScript MCP tools; and - affected range: `>= 1.5.0, <= 1.7.1`. The Python MCP advisories cover path traversal in specific Python MCP tool handlers. They do not cover the npm TypeScript `MCPServer` transport or its unwired security manager.

Exploitation Scenario

An adversary scanning internet-facing Node.js services identifies port 3000 (or any configured MCP port) accepting HTTP connections. They send a POST request with body {"jsonrpc":"2.0","method":"tools/list","id":1} and receive a full enumeration of registered tools with descriptions — no credentials required. They identify a tool wrapping shell execution or file system access, then invoke it via tools/call with crafted arguments, achieving arbitrary code execution as the server process. Because the server binds to :: by default, this is reachable from any network path that can reach the host. In internal AI agent deployments, an attacker who gains network adjacency (via a compromised host on the same VLAN or through SSRF from a web application) can pivot into the MCP server and exfiltrate credentials, trigger agent actions, or read application data registered as MCP resources — all in a single unauthenticated HTTP round-trip.

Weaknesses (CWE)

CWE-1188 — Initialization of a Resource with an Insecure Default: The product initializes or sets a resource with a default that is intended to be changed by the product's installer, administrator, or maintainer, but the default is not secure.

Source: MITRE CWE corpus.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Timeline

Published
June 18, 2026
Last Modified
June 18, 2026
First Seen
June 18, 2026

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