What is the best tool to prevent write access to the root on a Debian computer that can be turned on with a command?

I am on a Debian GNU/Linux, and i would like to be able to disable any write to the disk at some arbitrary time. It is ok, if i would need to reboot to re-enable the write access, but the best solution for me would be to not need to reboot… Continue reading What is the best tool to prevent write access to the root on a Debian computer that can be turned on with a command?

How can an ELF binary call a Windows API from WSL(2) to deploy a payload?

In September 2021 Black Lotus Labs (BLL) posted a blog entry discussing a payload loader that was:

written in Python
compiled to an ELF exe using PyInstaller in Debian in WSL
and "injected into a running process using Windows API cal… Continue reading How can an ELF binary call a Windows API from WSL(2) to deploy a payload?

Is DSA-1024 safe to sign package repositories ? What are the reasons?

I recently found that the latest release of a major Linux distribution (MX Linux) uses DSA-1024 in /etc/apt/trusted.gpg and in /etc/apt/trusted.gpg.d/*.gpg
It also probably uses SHA-1 as the signature algorithm (which is the most common on… Continue reading Is DSA-1024 safe to sign package repositories ? What are the reasons?

Researchers flag 7-years-old privilege escalation flaw in Linux kernel (CVE-2021-33909)

A vulnerability (CVE-2021-33909) in the Linux kernel’s filesystem layer that may allow local, unprivileged attackers to gain root privileges on a vulnerable host has been unearthed by researchers. “Qualys security researchers have been able to in… Continue reading Researchers flag 7-years-old privilege escalation flaw in Linux kernel (CVE-2021-33909)