Manipulating Network Traffic GMOB Practice Questions (Page 4)

Questions 16–20

1. 16application · medium

   An analyst is testing a mobile app that communicates with a backend API using JSON over HTTPS. The analyst wants to identify input validation vulnerabilities in the API by sending malformed data. Which approach is most effective for this task?

   • ACapture legitimate traffic, then use a fuzzing tool to replay the requests with mutated JSON payloads.
   • BAnalyze the app's source code to find validation logic.
   • CManually edit the JSON payload in a proxy and resend it once with a single malformed field.
   • DUse a network scanner to identify open ports on the API server.
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2. 17expert · hard

   An analyst is testing a mobile app that uses mutual TLS (mTLS) with a client certificate. The analyst has extracted the client certificate and private key from the app. Which step is necessary to intercept the traffic with a proxy?

   • AConfigure the proxy to present the extracted client certificate to the server during the TLS handshake.
   • BUse a VPN to route traffic through a server that logs all requests.
   • CUse a packet capture tool to capture the traffic and analyze the TLS handshake.
   • DInstall the proxy's CA certificate on the device and configure the proxy to decrypt traffic.
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4. 18application · medium

   During a security assessment, a tester intercepts a mobile app's login request and notices that the password is sent in plaintext within a JSON body over HTTPS. The tester wants to test whether the server enforces password complexity. Which manipulation is most appropriate?

   • AChange the username to another user's account and attempt to log in.
   • BReplay the same request with a weak password like '1234' and observe if the server accepts it.
   • CRemove the password field entirely from the request and observe the server's response.
   • DModify the password field to an empty string and see if the server returns an error.
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5. 19expert · hard

   A security tester is assessing a mobile app that uses a custom encryption scheme for its network traffic. The tester has captured a session and wants to replay it to test for replay protection. Which approach is most appropriate?

   • AModify the encrypted payload slightly and replay it to see if the server detects tampering.
   • BReplay the packets with a different source IP address.
   • CReplay the packets after a long delay to see if the server accepts them.
   • DReplay the exact captured packets to the server and observe if the server accepts them again.
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6. 20application · medium

   An analyst is testing an iOS app that uses certificate pinning. The analyst has a jailbroken device and wants to intercept HTTPS traffic to a specific API. The app uses URLSession with default pinning. Which technique is most effective?

   • AUse a DNS spoof to redirect the API domain to a local server that presents a self-signed certificate.
   • BInstall a proxy CA certificate in the system trust store and configure the device to use the proxy.
   • CUse a tool like SSL Kill Switch to disable certificate validation, then configure the proxy with a custom CA.
   • DUse a VPN to route traffic to a remote server that logs all requests without decryption.
   Reveal Solution Discussion Select an answer first