| Package | Affected versions | Patched versions |
|---|---|---|
| praisonai | ≥ 1.5.1, < 1.7.2 | 1.7.2 |
The published npm package praisonai exports an MCPSecurity helper described in source as:
MCP Security - Authentication, authorization, and rate limiting
Provides security policies for MCP servers.
Its AuthMethod type advertises five authentication methods:
export type AuthMethod = 'none' | 'api-key' | 'bearer' | 'basic' | 'oauth';
The authentication-policy evaluator, however, only validates credentials for api-key and bearer:
if (policy.auth.method === 'api-key' || policy.auth.method === 'bearer') {
const valid = policy.auth.validate
? await policy.auth.validate(token)
: this.validateApiKey(token);
if (!valid) {
return { allowed: false, reason: 'Invalid credentials' };
}
}
return { allowed: true, context: { authenticated: true } };
For basic and oauth, any non-empty Authorization header skips the supplied validate callback and returns allowed. A local PoV configures auth.validate to always return false; invalid api-key and bearer credentials are rejected, while invalid basic and oauth credentials are accepted without calling the validator.
This is a protection-mechanism failure in the exported npm MCP security helper. It is distinct from the separate issue that the npm MCPServer HTTP transport does not enforce authentication by default.
SecurityPolicy.auth accepts both a method and a validator:
auth?: { method: AuthMethod; validate?: (token: string) => Promise<boolean> };
extractToken() parses both Bearer and Basic headers:
if (auth.startsWith('Bearer ')) {
return auth.slice(7);
}
if (auth.startsWith('Basic ')) {
return auth.slice(6);
}
return auth;
But evaluatePolicy() only calls policy.auth.validate() for two methods:
if (policy.auth.method === 'api-key' || policy.auth.method === 'bearer') {
const valid = policy.auth.validate
? await policy.auth.validate(token)
: this.validateApiKey(token);
if (!valid) {
return { allowed: false, reason: 'Invalid credentials' };
}
}
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Scan my site freeThere is no validation branch for basic or oauth. After extracting any non-empty token, those methods fall through to the success return:
return { allowed: true, context: { authenticated: true } };
check() then ignores successful authentication context and returns a generic allowed result:
return { allowed: true, context: { authenticated: false } };
That context propagation issue is secondary. The security-relevant flaw is that invalid Basic/OAuth credentials are allowed at all.
This is not a claim that every MCPSecurity user must choose Basic or OAuth. The issue is that the API explicitly exposes those methods as authentication methods and accepts a validator callback for the policy, but the implementation does not call the validator for those methods.
The control cases prove the intended security behavior:
Authentication required.api-key credentials are denied as Invalid credentials.bearer credentials are denied as Invalid credentials.The only difference in the vulnerable cases is the selected advertised method. Invalid Basic/OAuth credentials should not become authenticated merely because the method is not listed in the two-method validation branch.
This also matches MCP authorization guidance. MCP servers acting as resource servers must validate received access tokens; receiving a token is not proof that it is valid or intended for the server.
Run from a local reproduction checkout:
node poc/pov_poc.js 1.7.1
The PoV:
npm:[email protected] into a temporary project with scripts disabled.MCPSecurity from the package root.authenticate policy per method.auth.validate callback that always returns false.api-key, bearer, basic, and oauth credentials.Observed output summary from evidence/pov-npm-1.7.1.json:
{
"package": "praisonai",
"version": "1.7.1",
"cases": [
{
"method": "api-key",
"validateCalls": 1,
"allowed": false,
"reason": "Invalid credentials"
},
{
"method": "bearer",
"validateCalls": 1,
"allowed": false,
"reason": "Invalid credentials"
},
{
"method": "basic",
"validateCalls": 0,
"allowed": true
},
{
"method": "oauth",
"validateCalls": 0,
"allowed": true
},
{
"method": "basic",
"authorizationHeaderPresent": false,
"validateCalls": 0,
"allowed": false,
"reason": "Authentication required"
}
],
"controlsPass": true,
"vulnerable": true
}
The PoV is local-only. It does not start a server, contact a third-party target, or use live credentials.
The PoV section above contains the local reproduction command, input, and decisive output.
A downstream application that uses MCPSecurity to protect an HTTP MCP transport, gateway, or equivalent tool/resource endpoint can believe it has enabled Basic or OAuth authentication while accepting any non-empty Authorization header.
Depending on the protected MCP tools and resources, this can allow an unauthenticated network caller to:
This report does not claim that npm PraisonAI wires MCPSecurity into the default MCPServer.startHttp() path. It is a library-level authentication bypass in an exported security component intended to protect MCP servers.
Suggested severity: High.
Rationale:
AV: the affected helper is intended to protect MCP server requests and equivalent HTTP security checks.AC: a single non-empty Basic or OAuth-style Authorization header is sufficient when such a policy is configured.PR: the bypass grants access without valid credentials.UI: no maintainer or user interaction is required after deployment.S: impact is within the PraisonAI-hosting service and its exposed MCP resources/tools.C: protected MCP resources or tool outputs may be disclosed.I: protected tool calls may perform state-changing actions depending on the registered tools; the score is conservative because the vulnerable helper is library-level and deployment-dependent.A: the PoV does not demonstrate availability impact.If a deployment protects high-impact write or execution tools with MCPSecurity, maintainers may reasonably score integrity higher.
Make authentication evaluation fail closed for every advertised method.
Recommended:
authenticate policies, call policy.auth.validate(token) whenever it is provided, regardless of auth.method.validateApiKey() for api-key when that behavior is explicitly intended.bearer and oauth, require a validator or a server-side token validation implementation; otherwise deny with a configuration error.basic, decode the Basic credential safely and pass the decoded username/password or raw credential to a validator; if no validator exists, deny.check() after a successful authenticate policy instead of replacing it with { authenticated: false }.api-key, bearer, basic, and oauth, and that each configured validator is called.Minimal fail-closed shape:
if (policy.type === 'authenticate') {
if (!policy.auth) return { allowed: false, reason: 'Authentication policy is not configured' };
const token = request.headers ? this.extractToken(request.headers) : null;
if (!token) return { allowed: false, reason: 'Authentication required' };
if (policy.auth.validate) {
const valid = await policy.auth.validate(token);
return valid
? { allowed: true, context: { authenticated: true } }
: { allowed: false, reason: 'Invalid credentials' };
}
if (policy.auth.method === 'api-key') {
return this.validateApiKey(token)
? { allowed: true, context: { authenticated: true } }
: { allowed: false, reason: 'Invalid credentials' };
}
return { allowed: false, reason: 'Authentication validator required' };
}
MervinPraison/PraisonAInpmpraisonaisrc/praisonai-ts/src/mcp/security.tsnode_modules/praisonai/dist/mcp/security.js1.7.1origin/main validated: 1ad58ca02975ff1398efeda694ea2ab78f20cf3esrc/praisonai-ts/package.json at origin/main: praisonai 1.7.1Suggested affected range:
npm:praisonai >= 1.5.1, <= 1.7.1
All published npm 1.x versions were swept locally:
1.0.0 through 1.5.0: the tested root export was unavailable or MCPSecurity was not exported as a constructor.1.5.1, 1.5.2, 1.5.3, 1.5.4, 1.6.0, 1.7.0, and 1.7.1: vulnerable.The package root re-exports this helper:
export {
MCPClient, createMCPClient, getMCPTools,
MCPServer, createMCPServer,
MCPSession as MCPSessionManager, createMCPSession,
MCPSecurity, createMCPSecurity, createApiKeyPolicy, createRateLimitPolicy,
type MCPClientConfig, type MCPSession, type MCPTransportType,
type MCPServerConfig, type MCPServerTool,
type SecurityPolicy, type SecurityResult
} from './mcp';
Visible PraisonAI advisories and prior submissions were checked. The closest public advisory is GHSA-98f9-fqg5-hvq5 / CVE-2026-34953, but that issue is distinct:
GHSA-98f9-fqg5-hvq5 affects the PyPI package and Python OAuthManager.validate_token().src/praisonai-ts/src/mcp/security.ts.True.The earlier npm MCPServer report is also distinct: it covers missing auth in the HTTP transport by default. This report covers a fail-open branch in the separate exported MCPSecurity helper when users attempt to add Basic/OAuth authentication.