In early 2022, Cisco revealed a major security vulnerability affecting its TelePresence CE software and RoomOS used by Cisco Touch 10 devices. This issue, tracked as CVE-2022-20793, allowed unauthenticated attackers to *impersonate legitimate devices* and pair with affected Cisco systems, gaining unauthorized access to sensitive communications hardware.

Let’s take an exclusive, step-by-step look at what went wrong, what it means for anyone using this hardware, and how attackers could exploit it in the real world.

What’s the Problem?

CVE-2022-20793 is due to *insufficient identity verification* during the device pairing process. When a new device (like the Cisco Touch 10 control panel) joins a video conferencing system (using TelePresence CE or RoomOS), the system is supposed to verify that it’s talking to the real thing—not an imposter.

Unfortunately, in the affected software versions, this process wasn’t checking the device’s true identity correctly. That opened the door for bad actors on the network to pretend they were a legitimate Cisco Touch 10 device and trick the system into pairing with them.

In Cisco’s Own Words

> *“An attacker could exploit this vulnerability by impersonating a legitimate device and responding to the pairing broadcast from an affected device.”*
— Cisco Security Advisory - CVE-2022-20793

Exploiting CVE-2022-20793

Let’s break this down into simple steps, just like an attacker would.

Listening for Pairing Broadcasts:

Affected Cisco devices broadcast a message to find legitimate Touch 10 devices trying to pair.

Impersonating the Device:

The attacker’s device receives the broadcast and responds *as if* it’s a real Cisco Touch 10. Since the pairing process doesn’t sufficiently verify identity, the attacker’s device gets paired.

Unauthorized Access:

Once paired, the attacker’s “fake” device can send commands, interact with the conferencing hardware, or access sensitive information.

A Simple Code Example

Below is a *very* basic example in Python, illustrating what a *simulated attacker* might do to respond to a pairing request.

import socket

# Listen for pairing broadcast (UDP)
UDP_IP = "..."
UDP_PORT = 500  # Example port for demo

sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sock.bind((UDP_IP, UDP_PORT))

print("Listening for pairing broadcasts...")

while True:
    data, addr = sock.recvfrom(1024)
    if b"PAIR_REQUEST" in data:
        print(f"Pairing request received from {addr}")

        # Craft a malicious response imitating a Touch 10 device
        fake_response = b"PAIR_RESPONSE;deviceID:touch10_fake;token:1234"
        sock.sendto(fake_response, addr)

        print(f"Sent fake pairing response to {addr}")

*Note: The actual protocol details and ports may differ; this is an illustrative example only.*

Control Video Conferences: Start, stop, or disrupt meetings.

- Access Sensitive Information: View meeting details, participant lists, or audio/video streams.

Launch Further Attacks: Use the compromised device to pivot deeper into the corporate network.

There are no workarounds. The only solution is to update the device software to the fixed version as soon as possible.

Mitigation and Recommendations

Cisco Security Advisory:
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ce-pairing-idver-xD5m7vUh

Conclusion

*CVE-2022-20793* is a stark reminder of how crucial identity verification is, especially in environments where hundreds of devices talk to each other without human interaction. By understanding the risks and knowing how attackers think, organizations can better defend their networks and keep communications private.

Stay updated. Stay secure.

*References:*
- Cisco Security Advisory, CVE-2022-20793
- NVD - CVE-2022-20793 Details

Timeline

Published on: 11/15/2024 15:34:33 UTC