Let's discuss some other voice security threats.
Your voicemail box holds a wealth of confidential
information just waiting to be discovered,
and a savvy hacker can make multiple attempts to reach a part of your voicemail
from where he can listen to your messages and even make expensive international
calls. But fear not, with a few simple measures,
you can protect your voicemail from prying eyes.
You could enforce a strict voicemail password policy so that end users are
forced to keep complex passwords and change them regularly.
None of the users should be allowed to keep a simple, default,
and repetitive voicemail password. Also, by restricting the types
of calls that your voicemail server can make, you can ensure that
only authorized calls are made.
For instance,
you could limit your voicemail to making only local or in network calls,
completely blocking access to long distance or international numbers.
Keep your secrets safe and sound with these easy to implement security
measures. The threat of a man‑in‑the‑middle attack, MitM, looms over VoIP
communications as well.
This cunning tactic involves intercepting and altering calls,
potentially stealing information, or changing the content of the call.
Unknowingly, both parties sends and receive traffic through the attacker's
computer, believing they are communicating solely with each other. This
occurs when the attacker manipulates Active Directory Domain Services, DNS
configuration, or other methods to redirect clients through their own
server. Fortunately,
Microsoft Teams has implemented measures to prevent such attacks on media
traffic. By using Secure Real‑time Transport Protocol,
SRTP,
Microsoft Teams encrypts the media stream and cryptographic keys
are negotiated using the team call signaling protocol, which
employs the highly secured TLS 1.2 and AES‑256 in GCM mode, encryption over UDP or TCP.