Are legacy phones a security risk?

[Tinov]

I'm a home user. I have a SIP-T18P, I'm not sure how old it is probably 10 years or more.

Is it safe to use on my home network? I don't care about encryption of calls or the like. I'm just worried that it might provide an entry point for a hacker.

Is there any up-to-date firmware available?

My network is thus:
The phone is attached to an unmanaged switch which also has a home PC (cable connection) a work-provided thin client (cable connection), and a wireless access point attached (mobile phones access the network via this). The switch is connected by cable to a home router which is a DHCP server. The phone is set to get IP address by DHCP. The network addresses in use are unrouteable (192.168.x.x). Service provider is Sipgate.

Any opinions or comment most welcome.

[Phil2021]

(08-19-2021 11:26 PM)Tinov Wrote:  I'm a home user. I have a SIP-T18P, I'm not sure how old it is probably 10 years or more.

Is it safe to use on my home network? I don't care about encryption of calls or the like. I'm just worried that it might provide an entry point for a hacker.

Is there any up-to-date firmware available?

My network is thus:
The phone is attached to an unmanaged switch which also has a home PC (cable connection) a work-provided thin client (cable connection), and a wireless access point attached (mobile phones access the network via this). The switch is connected by cable to a home router which is a DHCP server. The phone is set to get IP address by DHCP. The network addresses in use are unrouteable (192.168.x.x). Service provider is Sipgate.

Any opinions or comment most welcome.

If it is via NAT then it should not be reached from outside by an unsolicited connection. If you go to grc.com and find the Shields Up option, this allows you to scan all the common service ports, see if you have any open ports, if they all come back as stealth then you are quite safe from any outside attacks as they can't get to anything.

Of course nothing is 100% secure, if your router has security vulnerabilities then someone might be able to hack a route through to your local network, if the phone has a vulnerability they could hack into that (bypass the password) then download any contact lists or use your Sipgate credentials to make calls, but a lot of things have to line up for that to happen.

Hope that helps.

[Amelie Davis]

(08-19-2021 11:26 PM)Tinov Wrote:  I'm a home user. I have a SIP-T18P, I'm not sure how old it is probably 10 years or more.

Is it safe to use on my home network? I don't care about encryption of calls or the like. I'm just worried that it might provide an entry point for a hacker.

Is there any up-to-date firmware available?

My network is thus:
The phone is attached to an unmanaged switch which also has a home PC (cable connection) a work-provided thin client (cable connection), and a wireless access point attached (mobile phones access the network via this). The switch is connected by cable to a home router which is a DHCP server. The phone is set to get IP address by DHCP. The network addresses in use are unrouteable (192.168.x.x). Service provider is Sipgate.

Any opinions or comment most welcome.

Most legacy phone systems can only support a specific number of phones; expanding beyond that limit requires purchasing additional hardware. Aging phones can also compromise security. Once vendors stop providing patches, updates and bug fixes, you'll face elevated cybersecurity risks and potential compliance issues