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VoIP and WebRTC
Security Articles and News

Articles and security news about vulnerabilities and attacks affecting VoIP and WebRTC by Enable Security.

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Killing bugs … one vulnerability report at a time

Executive summary (TL;DR) We tell the story behind the latest FreeSWITCH advisories and how it all came together one sleepless night in April 2021 so that we ended up with 4 vulnerabilities that needed reporting. And then, one more vulnerability found due to a bug in our own software, SIPVicious PRO. We explain how these flaws were discovered, reported, fixed and what we ultimately learned through this process. What is this about?…

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One presentation at ClueCon and five security advisories for FreeSWITCH

The FreeSWITCH team has just published version v1.10.7 which fixes a number of security issues that we reported. If you use FreeSWITCH, please do upgrade to get these security updates. To learn about the background work that went into getting these security bugs squashed, follow Sandro’s talk called Killing bugs … one vulnerability report at a time. This will be presented at at ClueCon on Thursday, October 28th. Here are the titles of each advisory and a very short summary:…

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Why volumetric DDoS cripples VoIP providers and what we see during pentesting

Published on Oct 13, 2021 in ,

An epiphany Until a few days ago, I was of the opinion that simulating volumetric DDoS attacks is not something we should be doing. If you had asked us for such a test, we would have given you a negative answer. Ironically, we had been unwittingly simulating volumetric DDoS attacks while quietly ignoring our own results. But, it’s time to stop neglecting bandwidth saturation and start giving it the attention that it deserves.…

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Massive DDoS attacks on VoIP Providers and simulated DDoS testing

Published on Sep 24, 2021 in ,

VoIP.ms and other VoIP providers under DDoS attack At the time of writing, a major VoIP provider called VoIP.ms is under a distributed denial of service (DDoS) attack since over a week. As a result, they are unable to serve their customers with everyone and their dog complaining that they cannot connect to VoIP.ms’s SIP servers as well as other resources. At the same time, someone claiming to be part of the REvil ransomware group is blackmailing the provider.…

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Abusing SIP for Cross-Site Scripting? Most definitely!

Published on Jun 10, 2021 in , ,

Executive summary (TL;DR) SIP can be used as an attack vector for AppSec vulnerabilities such as cross-site scripting (XSS), potentially leading to unauthenticated remote compromise of critical systems. VoIPmonitor GUI had one such vulnerability which highlights this attack vector exceptionally well. The following writeup explores how persistent backdoor administrative access can be obtained by sending malicious SIP messages. This vulnerability was reported by Enable Security and fixed in VoIPmonitor GUI back in February 2021, using standard cross-site scripting protection mechanisms.…

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SIPVicious OSS v0.3.4 released with exit codes and automation features

We just made SIPVicious OSS v0.3.4 available, so go get it! Or install it via pip: pip install sipvicious --upgrade What’s new? Two main things: Exit codes, just like SIPVicious PRO’s Integration with Github Actions This release makes it much easier to use SIPVicious OSS within your CI/CD pipelines and other automation systems. One should, of course, read the documentation on automation for more information. But here’s an example script to get the idea of what can be done:…

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DEMO - An overview of the VoIP and RTC offensive security toolset, SIPVicious PRO

We pushed out a video that introduces the basics of SIPVicious PRO by demonstrating some of the attack tools and showing the building blocks for automating security testing of VoIP and WebRTC applications and infrastructure. What follows is a transcript of the video. Introduction Hello, I’m Sandro Gauci from Enable Security. In this video, I’d like to show you what we have been working on, SIPVicious PRO! Let’s start by introducing the tools.…

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SIPVicious PRO 6.0.0-beta.4 getting close to take-off!

This one’s a bit of a boring update for SIPVicious PRO. That’s because we’re getting to a stable place where flag names and values do not change too often. Which means, we’re getting out of beta rather soon! However, it is still a major update because we made a significant number of internal changes. For example, we standardized a number of flags to be the same across all tools. We discovered that we can minimize each tool’s flagset by making use of config flags such as --auth-config that allows you to configure behaviours specific to how SIPVicious handles authentication (e.…

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TADSummit Asia 2021 talk about SIPVicious Pro and the Demo Server

TADSummit is a great event where people from different backgrounds that are somehow involved in communications, contribute in various ways. I, personally, always look forward to see what’s coming up in the next TADSummit event. At the moment, TADSummit Asia presentations are currently being released on a daily basis on the main site. And last week, the presentation that I prepared was published! In the previous TADSummit, I had presented about why we need to bring an offensive approach to RTC security.…

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OpenSIPIt'01: Lessons learned, STIR/SHAKEN security testing and RFC 8760

Published on Apr 16, 2021

Executive summary (TL;DR) It was a great event, highly recommended if you’re a SIP developer. We developed new STIR/SHAKEN capabilities in SIPVicious PRO. And we found some vulnerabilities during the event that got fixed in the process. What was OpenSIPIt#01 about? This week the humble security researchers from Enable Security participated in OpenSIPIt#01, an online event run by the community to test interoperability across various independent open-source SIP implementations especially when it comes to new RFCs.…

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