Skip to content

Initial Access - Advanced Techniques

Trusted Relationship

Also look at the "Procedure examples" in the MITRE ATT&CK technique.

Supply Chain Compromise

Also look at the References in the MITRE ATT&CK technique (and their sub-techniques).

Application software

SolarWinds

A major incident with national security implications.

Linux xz compression library

Over a period of over two years, an attacker worked as a diligent, effective contributor to the xz compression library, eventually being granted commit access and maintainership. Using that access, they installed a very subtle, carefully hidden backdoor into liblzma, a part of xz that also happens to be a dependency of OpenSSH sshd on Debian, Ubuntu, Fedora, and other systemd-based Linux systems. That backdoor gives the attacker the ability to run an arbitrary command on the target system without logging in: unauthenticated, targeted remote code execution.

This attack was publicly disclosed on March 29, 2024 and it marks a watershed moment in open source supply chain security.

Because the backdoor was discovered before the malicious versions of xz Utils were added to production versions of Linux, “it's not really affecting anyone...BUT that's only because it was discovered early due to bad actor sloppiness. Had it not been discovered, it would have been catastrophic to the world.”

Interesting examples

Software development

You develop software and you could unwillingly distribute malicious software to your customers:

Firmware and routers

Defense

Simple yet important events:

Analyses