Helol Tunnel: Covert Channel Exploitation of TLS Extensibility & Privacy Features

Name: Helol Tunnel: Covert Channel Exploitation of TLS Extensibility & Privacy Features
Uploaded: 2026-10-05T07:00:25.218653+00:00
Duration: 761 s
Description: The Helol tunnel exploits how TLS Client Hello packets allow for combinatorial arrangements (selection and permutation) of cryptographic parameters like cipher suites. This method enables covert data exfiltration and command-and-control communication by encoding stolen information into the order of these parameters, evading modern firewalls.

The Helol tunnel exploits how TLS Client Hello packets allow for combinatorial arrangements (selection and permutation) of cryptographic parameters like cipher suites. This method enables covert data exfiltration and command-and-control communication by encoding stolen information into the order of these parameters, evading modern firewalls.

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