Impersonating a Windows Enterprise Admin with a Certificate: Kerberos PKINIT from Linux

This is about a serious misconfiguration of a Windows Public Key Infrastructure integrated with Active Directory: If you can edit certificate templates, you can impersonate the Active Directory Forests's Enterprise Administrator by logging on with a client certificate. You have a persistent credential that will also survive the reset of this admin's password. In the … Continue reading Impersonating a Windows Enterprise Admin with a Certificate: Kerberos PKINIT from Linux

Locating Domain Controllers and Spoofing Active Directory DNS Servers

Last year, hackthebox let me test something I have always found fascinating - and scary: You can impersonate any user in a Windows Active Directory Forest if you have control over the certificate templates of an AD-integrated Windows Public Key Infrastructure: Add extended key usages for smartcard logon to the template, enroll for the certificate, … Continue reading Locating Domain Controllers and Spoofing Active Directory DNS Servers

Helpline @ hackthebox: Injecting an EFS Recovery Agent to Read Encrypted Files

Another great machine has been retired on hackthebox.eu - Helpline by @egre55! Here is my 'silly' unintended way to root the box: You can get both the encrypted user and root flag via the cumbersome web RCE alone - if you wait for a legit user to just look at the file. This is unlikely … Continue reading Helpline @ hackthebox: Injecting an EFS Recovery Agent to Read Encrypted Files

Sizzle @ hackthebox – Unintended: Getting a Logon Smartcard for the Domain Admin!

My writeup - how to pwn my favorite box on hackthebox.eu, using a (supposedly) unintended path. Sizzle - created by @mrb3n813 and @lkys37en - was the first box on HTB that had my favorite Windows Server Role - the Windows Public Key Infrastructure / Certification Authority. This CA allows a low-privileged user - amanda - … Continue reading Sizzle @ hackthebox – Unintended: Getting a Logon Smartcard for the Domain Admin!

Simple Ping Sweep, Port Scan, and Getting Output from Blind Remote Command Execution

Just dumping some quick and dirty one-liners! These are commands I had used to explore locked-down Windows and Linux machines, using bash or powershell when no other binaries were available or could be transferred to the boxes easily. Trying to ping all hosts in a subnet Linux for i in $(seq 1 254); do host=192.168.0.$i; … Continue reading Simple Ping Sweep, Port Scan, and Getting Output from Blind Remote Command Execution

Echo Unreadable Hex Characters in Windows: forfiles

How to transfer small files to a locked-down Windows machine? When there is no option to copy, ftp, or http GET a file. When powershell is blocked so that you can only use Windows cmd commands? My first choice would be to use certutil: certutil is a built-in tool for certificate and PKI management. It … Continue reading Echo Unreadable Hex Characters in Windows: forfiles

Ethereal @ hackthebox: Certificate-Related Rabbit Holes

This post is related to the 'insanely' difficult hackthebox machine Ethereal (created by egre55 and MinatoTW) that was recently retired. Beware - It is not at all a full comprehensive write-up! I zoom in on openssl, X.509 certificates, signing stuff, and related unnecessary rabbit holes that were particularly interesting to me - as somebody who … Continue reading Ethereal @ hackthebox: Certificate-Related Rabbit Holes

Certificates and PKI. The Prequel.

Some public key infrastructures run quietly in the background since years. They are half forgotten until the life of a signed file has come to an end - but then everything is on fire. In contrast to other seemingly important deadlines (Management needs this until XY or the world will come to an end!) this … Continue reading Certificates and PKI. The Prequel.

Modbus Server on Raspberry Pi as Babelfish for UVR16x2

Our main data logger is the Control and Monitoring Interface of the freely programmable controller UVR16x2. There are two pieces of hardware you need for logging - the actual control unit and the logger connected to the controller via the CAN bus. This 'architecture' might be due to historical reasons, but I like the separation … Continue reading Modbus Server on Raspberry Pi as Babelfish for UVR16x2

Unintended 2nd Order SQL Injection

Why I am not afraid of the AI / Big Data / Cloud powered robot apocalypse. SQL order injection means to run custom SQL queries through web interfaces because the input to the intended query is not sanitized, like appending the infamous ' OR '1'='1 to a user name or search term. It is 2nd … Continue reading Unintended 2nd Order SQL Injection