Description

Detects network connections in Swift applications that use insecure TCP configuration. Using unencrypted TCP connections can expose sensitive data to network sniffing and man-in-the-middle attacks, as data is transmitted in plaintext.

Detection Strategy

• Identifies creation of NWConnection objects in Swift code

• Checks if the connection protocol parameter is set to '.tcp' or derives from an unsafe variable

• Reports a vulnerability when a NWConnection is configured to use plain TCP without encryption

Vulnerable code example

import Network

let host = NWEndpoint.Host("example.com")
let port = NWEndpoint.Port(1234)!

// VULNERABLE: Using unencrypted TCP connection exposes data to interception
let insecureConnection = NWConnection(host: host, port: port, using: .tcp)
insecureConnection.start(queue: .main)...

✅ Secure code example

import Network

let host = NWEndpoint.Host("example.com")
let port = NWEndpoint.Port(1234)!

// SECURE: Using TLS encryption to protect data in transit
let secureConnection = NWConnection(host: host, port: port, using: .tls)
secureConnection.start(queue: .main)...