BloodHound data collection, aka Sharphound, is quite a complex beast.
When giving BloodHound workshops, the part where I get the most questions is always data collection.
How is the BloodHound data collected? What methods do what? Who am I talking to? How do I fly under the radar? Continue reading “DogWhisperer’s SharpHound Cheat Sheet”
Category: Misc
BSI veröffentlicht Hardening Guide, Protokollierungs-Empfehlung und zugehörige GPOs für Windows 10 im Rahmen der SiSyPHuS-Studie
Wir freuen uns, dass das Bundesamt für Sicherheit in der Informationstechnik (BSI) im Rahmen des gemeinsam mit ERNW durchgeführten SiSyPHuS Win10-Projekts (Studie zu Systemintegrität, Protokollierung, Härtung und Sicherheitsfunktionen in Windows 10) heute (ca. 10 Uhr) die nächsten drei Arbeitspakete veröffentlicht:
- Empfehlung zur Härtung von Windows 10 mit Bordmitteln
- Empfehlung zur Konfiguration der Protokollierung in Windows 10
- Gruppenrichtlinien zu den Konfigurationsempfehlungen für Härtung und Protokollierung für Windows 10
In den Dokumenten finden sich unterschiedliche Empfehlungen für Domänenmitglieder (mit normalem und mit hohem Schutzbedarf) und Einzelplatzrechner. Die Dokumente bauen auf den Empfehlungen von Microsofts Security Baseline und dem CIS Benchmark für Windows 10 auf und ergänzen diese in von Microsoft und CIS nicht betrachteten Bereichen oder modifizieren sie dort, wo es aus Erfahrung von ERNW im Hardening von Windows-Systemen sinnvoll ist.
Sie finden die Dokumente hier.
Wir hoffen, damit zur Sicherheit von Windows-Umgebungen beitragen zu können, und wünschen Ihnen viel Spaß bei der Lektüre!
German Federal Office for Information Security (BSI) Publishes Hardening Guideline, Logging Guideline And Related GPOs for Windows 10
We are happy to announce that today the BSI publishes several documents that ERNW created as part of the long-term SiSyPHuS Win10-Project (ger: “Studie zu Systemintegrität, Protokollierung, Härtung und Sicherheitsfunktionen in Windows 10”, en: “Study on System Integrity, Logging, Hardening and Security relevant Functionality in Windows 10”):
- Hardening Guideline
- Logging Guideline
- GPOs for the Guidelines
The guidelines are built on recommendations from Microsoft´s Security Baseline, CIS Benchmarks and ERNW´s expertise.
You can find the documents and GPOs here.
Let’s make the Windows world a safer place, and have fun reading!
Cheers,
Friedwart.
Continue readingOf Corona, Buggy Audio Drivers and Industrial Espionage
The Situation
Last year, the CISO of a customer sent me a laptop for analysis. The reason was that he feared the company could have been victim of industrial espionage. Starting in spring 2020, the IT help desk got several employee laptops with full hard drives, caused by a huge amount of audio recordings. The audio files contained recordings even of highly sensitive telephone conferences. An automated scan on all employee computers for such audio recordings showed that about 300 devices were affected. Continue reading “Of Corona, Buggy Audio Drivers and Industrial Espionage”
Continue readingfpicker: Fuzzing with Frida
Introduction
In this post, I will introduce fpicker. Fpicker is a Frida-based coverage-guided, mostly in-process, blackbox fuzzing suite. Its most significant feature is the AFL++ proxy mode which enables blackbox in-process fuzzing with AFL++ on platforms supported by Frida. In practice, this means that fpicker enables fuzzing binary-only targets with AFL++ on potentially any system that is supported by Frida. For example, it allows fuzzing a user-space application on the iOS operating system, such as the Bluetooth daemon bluetoothd – which was part of the original motivation to implement fpicker.
Continue reading “fpicker: Fuzzing with Frida”
ERNW Whitepaper 71 – Analysis of Anti-Virus Software Quarantine Files
I am glad to announce the release of the ERNW whitepaper 71 containing information about quarantine file formats of different AV software vendors. It is available here.
Anti-Virus Software
I took quarantine files from real-life incidents and created some in a lab environment. Afterwards I tried to identify metadata, like timestamps, path names, malware names, and the actual malicious file in the quarantine files. One goal was to use this information to support our incident analyses: Using the results, we can now easily create timelines showing information about quarantined files, extract the detected malware, and sometimes even find information about processes that created the malicious files. Continue reading “ERNW Whitepaper 71 – Analysis of Anti-Virus Software Quarantine Files”
Continue readingHaving Fun with Google MDM Solution
It’s Friday, you managed to escape for a couple of hours from a busy working day to see a doctor. Now you have to wait in a boring waiting room at the clinic until it’s your turn to see her majesty. What would you like to do in this time? Answer pending business emails, get lost in social media, or choose a new theme to make your iPhone look awesome? What about: all of the above? It’s nice to have everything on your iPhone: MDM enrollment to access business data, in addition to jailbreak for device freedom. However, MDM solutions ban jailbroken devices, because they are not secure enough to handle sensitive business data. And so, cat and mouse games of jailbreak detection/bypass between MDM solutions and some users develop.
In this blogpost, I highlight how this cat and mouse game with Google’s MDM solution “Google Endpoint Management” is currently going. First, I explain how to bypass jailbreak detection of Google’s MDM solution. Then I show how to manipulate MDM enforced policies on your MDM-enrolled jailbroken device. Since these actions have negative impacts on your device’s security, we’ll also discuss how attackers can exploit this insecure setup to steal business data.
Continue reading “Having Fun with Google MDM Solution”
Continue readingPentesting the ELK Stack
With this blog post, I will provide information on how to proceed when testing ELK Stack landscapes. Information regarding the exploitation of the ELK Stack is very rare on the internet. Therefore, following article aims to provide you with some approaches that can be useful during a penetration test. Continue reading “Pentesting the ELK Stack”
Continue readingRoot Cause Analysis of a Heap-Based Buffer Overflow in GNU Readline
In the last blog post, we discussed how fuzzers determine the uniqueness of a crash. In this blog post, we discuss how we can manually triage a crash and determine the root cause. As an example, we use a heap-based buffer overflow I found in GNU readline 8.1 rc2, which has been fixed in the newest release. We use GDB and rr for time-travel debugging to determine the root cause of the bug.
Continue reading “Root Cause Analysis of a Heap-Based Buffer Overflow in GNU Readline”
Continue readingSecurity Advisories for SolarWinds N-Central
How Fuzzers Decide if a Crash is Unique
This blogpost sheds some light on how fuzzers handle crash deduplication and what a unique crash is for a fuzzer. For this, we take a look at two contrived examples and compare the unique crashes identified by AFL++ and honggfuzz.
Continue reading “How Fuzzers Decide if a Crash is Unique”
Continue reading