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A Novel DoS Vulnerability affecting WebRTC Media Servers

Published on Jun 25, 2024 in , , ,

Executive summary (TL;DR) A critical denial-of-service (DoS) vulnerability has been identified in media servers that process WebRTC’s DTLS-SRTP, specifically in their handling of ClientHello messages. This vulnerability arises from a race condition between ICE and DTLS traffic and can be exploited to disrupt media sessions, compromising the availability of real-time communication services. Mitigations include filtering packets based on ICE-validated IP and port combinations. The article also indicates safe testing methods and strategies for detecting the attack.…

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Exploiting CVE-2022-0778, a bug in OpenSSL vis-à-vis WebRTC platforms

Executive summary (TL;DR) Exploiting CVE-2022-0778 in a WebRTC context requires that you get a few things right first. But once that is sorted, DoS (in RTC) is the new RCE! How I got social engineered into looking at CVE-2022-0778 A few days ago, Philipp Hancke, self-proclaimed purveyor of the dark side of WebRTC, messaged me privately with a very simple question: “are you offering a DTLS scanner by chance?” He explained how in the context of WebRTC it would be a bit difficult since you need to get signaling right, ICE (that dance with STUN and other funny things) and finally, you get to do your DTLS scans.…

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If SIPVicious gives you a ring…

Note: SIPVicious version 0.28 is out, go get it. I like to keep an eye on the social media and Google alerts for SIPVicious and in the last few months I noticed a rise in mentions of the tools. Specifically, a number of Korean twitter users (who have their service with KT, a VoIP service provider) complaining about receiving a call from a caller-id showing ‘SIPVicious’. After contacting a Korean friend, this led to an interview by a reporter for an article that was published on a Korean tech news site Boan News.…

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