VoIP: SIP-over-TLS and sRTP: ALE

ALE was part of Alcatel-Lucent but was sold before the merger with Nokia. Today, ALE sells its phones under the Nokia brand ‘Alcatel-Lucent Enterprise’. Complicated? Do not confuse this company with another licensee of the Nokia brand ‘Alcatel’: ATLINKS who rebrands SIP phones from VTech. Complicated? Do not confuse those with ‘Alcatel Mobile’, again a licensee: TCL, who create their own GSM mobile phones. Complicated? ALE has their own platforms (OXE and OXO), and normally their phones work only with that. However, ALE bought Sipwise, who need Open-SIP phones. So, ALE created a special model range of their desk phones, the Cloud Edition (CE). Now, that is complicated! Thanks to Sipwise, I was able to get such a phone with an early production firmware. My contacts were extremely cooperative and fixed all of my several findings in weeks. However, the question remains, when this Cloud Edition is released, how does one get the latest firmware update?

Last tested firmware

1.51.02
retested in Dec. 2019 with 1.52.04

Configuration

Password: admin/123456
has to be changed after first use
HTTPS: enabled on default
no HTTP server, you have to go for https://ip
Update: Web → Maintenance → Binary Upgrade
Trust Anchors: Web → Maintenance → Certificate Management
Web → Settings → SIP → Advanced → SIPs Peer Verify: Enable
SIP-URI User: Web → Settings → SIP → Account 1 → Device URI
SIP-URI Host: Web → Settings → SIP → Account 1 → SIP server
Web → Settings → SIP → Account 1 → Server type: Asterisk
SIP-over-TLS: Web → Settings → SIP → Account 1 → Transport mode: TLS
Web → Settings → SIP → Account 1 → SIP server port: 5061
SDES-sRTP: Web → Settings → SIP → Account 1 → Srtp working mode: Best effort
which is RTP/AVP + RTP/SAVP = sRTP is second; therefore Digium Asterisk (and DUStel which use Asterisk) do not go for sRTP
Web → Settings → SIP → Account 1 → Srtp working mode: Strict
which is RTP/SAVP

Software Bugs

DNS-SRV: requires the Outbound Proxy to be set, and its port set to 0
DNS-NAPTR: missing
Audio: always does Discontinuous Transmission (DTX) even when Voice-Activity Detection (VAD) is disabled
NTP: FQDN may not start with a digit, like 2.pool.ntp.org
Mitigation: use a domain which starts with a char, like pool.ntp.org

Security

Bugs: requires a private key signed by the same trust anchor as your server fixed in Oct. 2019 with firmware 1.52
Privacy: device phones home to
  • rps.ce.al-enterprise.com
  • ce.al-enterprise.com
  • dev.eds.sipwise.com
  • eds.sipwise.at
Mitigation: Web → Settings → Network → DM → DM URL: any value
SIP messages contain MAC
Mitigation: unknown
Responsible Disclosure: via PSIRT team
Firmware Update: missing Automation
missing Newsletter

Miscellaneous

Model Range

Power Supply

5 V 1 A, Coaxial: 3.4 mm × 1.3 mm

back to the other phones.