Please read carefully and check if the version of your Zammad system is affected by this vulnerability. Please send information regarding vulnerabilities in Zammad to: security at zammad.com
Zammads WebSocket server crashes when messages in non-JSON format are sent by an attacker. The message format is not properly checked and parsing errors not handled. This leads to a crash of the service process.
Special 🙏 and 🤘 and ❤️ to:
N: Martin von Wittich
D: Security Researcher
This vulnerability is fixed in the latest versions of Zammad and it is recommended to upgrade to one of these.
Fixed releases can be found at:
Or just update your Zammad if installed via OS package manager.
Online version of this advisory: https://zammad.com/news/security-advisory-zaa-2020-06
Send all remarks to security issues to security @ zammad.com.