EUVD-2026-23300
GHSA-353c-v8x9-v7c3
Severity by source
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Primary rating from GitHub Advisory · only source for this CVE.
CVSS VectorGitHub Advisory
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Lifecycle Timeline
4Blast Radius
ecosystem impact- 89 npm packages depend on mcp-framework (87 direct, 2 indirect)
Ecosystem-wide dependent count for version 0.2.22.
DescriptionGitHub Advisory
Summary
The readRequestBody() function in src/transports/http/server.ts concatenates HTTP request body chunks into a string with no size limit, allowing a remote unauthenticated attacker to crash the server via memory exhaustion with a single large HTTP POST request.
Details
File: src/transports/http/server.ts, lines 224-240
private async readRequestBody(req: IncomingMessage): Promise<any> {
return new Promise((resolve, reject) => {
let body = '';
req.on('data', (chunk) => {
body += chunk.toString(); // No size limit
});
req.on('end', () => {
try {
const parsed = body ? JSON.parse(body) : null;
resolve(parsed);
} catch (error) {
reject(error);
}
});
req.on('error', reject);
});
}A maxMessageSize configuration value exists in DEFAULT_HTTP_STREAM_CONFIG (4MB, defined in src/transports/http/types.ts line 124) but is never enforced in readRequestBody(). This creates a false sense of security.
PoC
Local testing with 50MB POST payloads against the vulnerable readRequestBody() function:
| Trial | Payload | RSS growth | Time | Result |
|---|---|---|---|---|
| 1 | 50MB | +197MB | 42ms | Vulnerable |
| 2 | 50MB | +183MB | 46ms | Vulnerable |
| 3 | 50MB | +15MB | 43ms | Vulnerable |
| 4 | 50MB | +14MB | 32ms | Vulnerable |
| 5 | 50MB | +65MB | 38ms | Vulnerable |
Reproducibility: 5/5 (100%)
Impact
- Denial of Service: Any mcp-framework HTTP server can be crashed by a single large POST request to /mcp
- No authentication required: readRequestBody() executes before any auth checks (auth is opt-in, default is no auth)
- Dead config: maxMessageSize exists but is never enforced, giving a false sense of security
- Affected: All applications using mcp-framework HttpStreamTransport (60,000 weekly npm downloads)
CWE-770: Allocation of Resources Without Limits or Throttling Suggested CVSS 3.1: 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
Suggested Fix
Enforce maxMessageSize in readRequestBody():
private async readRequestBody(req: IncomingMessage): Promise<any> {
const maxSize = this._config.maxMessageSize || 4 * 1024 * 1024;
return new Promise((resolve, reject) => {
let body = '';
let size = 0;
req.on('data', (chunk) => {
size += chunk.length;
if (size > maxSize) {
req.destroy();
reject(new Error('Request body too large'));
return;
}
body += chunk.toString();
});
// ...
});
}Disclosure Timeline
This report follows coordinated disclosure. I request a 90-day window before public disclosure.
Reporter: Raza Sharif, CyberSecAI Ltd (contact@agentsign.dev)
Analysis
Summary
The readRequestBody() function in src/transports/http/server.ts concatenates HTTP request body chunks into a string with no size limit, allowing a remote unauthenticated attacker to crash the server via memory exhaustion with a single large HTTP POST request.
Details
File: src/transports/http/server.ts, lines 224-240
private async readRequestBody(req: IncomingMessage): Promise<any> {
return new Promise((resolve, reject) => {
let body = '';
req.on('data', (chunk) => {
body += chunk.toString(); // No size limit
});
req.on('end', () => {
try {
const parsed = body ? JSON.parse(body) : null;
resolve(parsed);
} catch (error) {
reject(error);
}
});
req.on('error', reject);
});
}A maxMessageSize configuration value exists in DEFAULT_HTTP_STREAM_CONFIG (4MB, defined in src/transports/http/types.ts line 124) but is never enforced in readRequestBody(). This creates a false sense of security.
PoC
Local testing with 50MB POST payloads against the vulnerable readRequestBody() function:
| Trial | Payload | RSS growth | Time | Result |
|---|---|---|---|---|
| 1 | 50MB | +197MB | 42ms | Vulnerable |
| 2 | 50MB | +183MB | 46ms | Vulnerable |
| 3 | 50MB | +15MB | 43ms | Vulnerable |
| 4 | 50MB | +14MB | 32ms | Vulnerable |
| 5 | 50MB | +65MB | 38ms | Vulnerable |
Reproducibility: 5/5 (100%)
Impact
- Denial of Service: Any mcp-framework HTTP server can be crashed by a single large POST request to /mcp
- No authentication required: readRequestBody() executes before any auth checks (auth is opt-in, default is no auth)
- Dead config: maxMessageSize exists but is never enforced, giving a false sense of security
- Affected: All applications using mcp-framework HttpStreamTransport (60,000 weekly npm downloads)
CWE-770: Allocation of Resources Without Limits or Throttling Suggested CVSS 3.1: 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
Suggested Fix
Enforce maxMessageSize in readRequestBody():
private async readRequestBody(req: IncomingMessage): Promise<any> {
const maxSize = this._config.maxMessageSize || 4 * 1024 * 1024;
return new Promise((resolve, reject) => {
let body = '';
let size = 0;
req.on('data', (chunk) => {
size += chunk.length;
if (size > maxSize) {
req.destroy();
reject(new Error('Request body too large'));
return;
}
body += chunk.toString();
});
// ...
});
}Disclosure Timeline
This report follows coordinated disclosure. I request a 90-day window before public disclosure.
Reporter: Raza Sharif, CyberSecAI Ltd (contact@agentsign.dev)
FortiOS and FortiProxy contain an authentication bypass via the Node.js websocket module allowing unauthenticated remote
Eval injection vulnerability in the internals.batch function in lib/batch.js in the bassmaster plugin before 1.5.2 for t
Flowise version 3.0.5 contains a remote code execution vulnerability in the CustomMCP node. The mcpServerConfig paramete
Node.js 8.5.0 before 8.6.0 allows remote attackers to access unintended files, because a change to ".." handling was inc
An issue was discovered in the node-serialize package 0.0.4 for Node.js. Rated critical severity (CVSS 9.8), this vulner
Directory traversal vulnerability in the st module before 0.2.5 for Node.js allows remote attackers to read arbitrary fi
Multiple SQL injection vulnerabilities in the Manage Accounts page in the AccountManagement.asmx service in the Solarwin
The JS-YAML module before 2.0.5 for Node.js parses input without properly considering the unsafe !!js/function tag, whic
Directory traversal vulnerability in lib/app/index.js in Geddy before 13.0.8 for Node.js allows remote attackers to read
Credential-harvesting malware compromised 84 versions of 42 TanStack npm packages on 2026-05-11 via chained GitHub Actio
Eval injection vulnerability in index.js in the syntax-error package before 1.1.1 for Node.js 0.10.x, as used in IBM Rat
The HTTP server in Node.js 0.10.x before 0.10.21 and 0.8.x before 0.8.26 allows remote attackers to cause a denial of se
Same technique Denial Of Service
View allShare
External POC / Exploit Code
Leaving vuln.today