XZ backdoor: Hook analysis

In their first article on the XZ backdoor, Kaspersky researchers analyzed its code from initial infection to the function hooking it performs. As they mentioned then, its initial goal was to successfully hook one of the functions related to RSA key manipulation.

In this article, the research team will focus on the backdoor’s behaviour inside OpenSSH, specifically OpenSSH portable version 9.7p1 – the most recent version at this time. To better understand what’s going on, they recommend you to read Baeldung’s article about SSH authentication methods and JFrog’s article about privilege separation in SSH.

Read more…
Source: Kaspersky

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