Anatomy of a Linux container rootkit
This year I gave a talk at the Easterhegg 2019 about a Linux kernel rootkit that can handle containers. I mainly presented my Bachelor work from 2017 with some improvements.
Details of a logrotate race-condition
Logrotate is prone to a race-condition on systems with a log directory that is in control of a low privileged user. A malicious user could trick logrotate to create files in any directory if it is executed as root. This might lead into a privileged escalation.
Abusing a race condition in logrotate to elevate privileges
Together with a friend we took part of the Capture The Flag at the 35C3. One challenge was that one:
Logrotate is designed to ease administration of systems that generate large numbers of log files. It allows automatic rotation, compression, removal, and mailing of log files. Each log file may be handled daily, weekly, monthly, or when it grows too large. It also gives you a root shell.
Merry Christmas
I wish you a merry christmas and a happy new year.
What the hack is "E-Brief"
This week I received an email from my bank company. They advertised that they are cooperating with the "Post"(Austrian mailprovider) and recommended to use "E-Brief" for notifications from them. My first thought was: "it's E-Mail". Because E-Brief translated from german means: "E-Mail". So I took a look in the FAQ's from the Post and they wrote things like(translated from German):
Your E-"Letter Box" from everywhere
High security
Fourth Anniversary
This blog really became 4 years old. When I started to write it was mostly for practicing written english. But my intention was always to give something back to the open-source community. I failed terribly with the first point. My english is as bad as it was before, but I have readers and get responses to some articles. It seems that I didn't failed with "giving something back to the open-source community".
Thank you to all my readers.
Full Disclosure: Remote-Command-Execution in PHKP
Overview
- System affected: PHKP
- Software-Version: including commit 88fd9cfdf14ea4b6ac3e3967feea7bcaabb6f03b
- User-Interaction: Not required
- Impact: Remote-Code-Execution
- CVE: CVE-2018-1000885
Detailed Description
According to the project-page "PHKP is an implementation of the OpenPGP HTTP Keyserver Protocol (HKP) in PHP".
Happy 20 Birthday to Nmap
The legendary portscanner nmap was released 20 years ago in Phrack #51. Happy Birthday nmap.
Happy Sysadminday
Sysadmins are the heros who bring back our cat-pictures from the heights of the filesystem-tree. So let's honour our firefighters of the internet.