Checking for Hafnium or other groups impact from Exchange…

Introduction

On March 2^nd, 2021 at ~6pm GMT Microsoft released an out of band update to all version of exchange from 2010 through to 2019. This was in response to a range of vulnerabilities which had been abused (a 0-day) by a threat actor (coined by MS as HAFNIUM).

For more info from MS please see the following:

https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/

Key CVEs

Key CVES include:

CVE-2021-26855, CVE-2021-26857, CVE-2021-26858, and CVE-2021-27065. Read more “Checking for Hafnium or other groups impact from Exchange Abuse” →

Exchange 2010 Rapid Analysis for IOCs

Purpose

With the Hafnium “incidents” and Exchange vulnerabilities I wanted to help people with ruling in or out compromise of their Exchange 2010 environments. At the time of writing, I don’t believe that Hafnium affected Exchange 2010 via the reported kill chain, I believe that BEC would be required but this is a theory, my general view is Exchange 2010 might be ‘safe’ from this kill chain. This is due to the initial stage leveraging CVE-2021-26855 which is an SSRF vulnerability which only affectes the new architecture (2013+). However, this is an unsupported platform so I wanted to help with some baselines and talk about how I would approach ruling compromise in or out (at least with regards to these vulnerabilities). The key impact area is a web shell. I’ve made some baselines to help people look for abnormalities.

Disclaimer

This document was made with limited time and without full Whitebox access to source code and engineering expertise. The areas we are checking for IOCs appear to make logical sense, but the OS and APP (Exchange 2010) are unsupported, and we are not the vendor. So, I am afraid your hunting responsibility is on you, this is just my opinions and thoughts from a very fast analysis. Use at your own risk. Read more “Exchange 2010 Rapid Analysis for IOCs” →

vSphere Unauthenticated Remote Code Execution Vulnerability – VMSA-2021-0002

For vendor guidance please see:

https://www.vmware.com/security/advisories/VMSA-2021-0002.html

CVE Refs: CVE-2021-21972, CVE-2021-21973, CVE-2021-21974

Introduction

There’s a new unauthenticated remove code execution (RCE) in vSphere 6.5, 6.7 and 7.0 which has just dropped. There’s a vendor patch and currently there is no known public exploit however the hunt will now be on and I can imagine that it’s hours and days until this is in the wild rather than weeks or months.

Threat Modelling 101

What is a threat?

https://csrc.nist.gov/glossary/term/threat

According to those clever people at NIST it is:

“Any circumstance or event with the potential to adversely impact organizational operations (including mission, functions, image, or reputation), organizational assets, or individuals through an information system via unauthorized access, destruction, disclosure, modification of information, and/or denial of service. Also, the potential for a threat-source to successfully exploit a particular information system vulnerability.” Read more “Threat Modelling 101” →

Combating Cyber Crime: Should we really be charging to…

Sensational Press or Cyber War Mongering?

I do not know Mr Martin, but I would assume that his role at NCSC and GCHQ would have given him a good insight into the realities of cybercrime, cyber terrorism, nation state affairs and how to effectively defend against cyber criminals (and other threat actors) so please read this blog as it is intended, it’s an analysis on the quoted statements and reporting style and general view of mine about current cyber war rhetoric, not an analysis of the person. Why am I writing this? Well, I am seeing an increased level of FUD, snake oil and cyber war rhetoric and I wanted to share some of my thoughts, opinions, and ideas in this space. For it is far too easy to call for war and in cyberspace do we even know what that means? Read more “Combating Cyber Crime: Should we really be charging to cyber war?” →

Extortion and Ransomware – A lethal Combination

A Brief History of Ransomware

Ransomware is not that new, I remember back during the msblaster incident I said to a friend, it is a good job whoever wrote this worm was not evil because they would have simply encrypted or deleted all the data post infection. Hell, I can barely remember when that was, I think it was late 2003. Ransomware has been around since the 1980s but not quite in its modern form (it started with the AIDS malware scam). Fast forward to the mid 2000’s and criminals were using encryption but that wasn’t a norm and things only really started to take a bad turn around 2012/2013 with Cryptolocker. The next major global events were WannaCry, NotPetya and Badrabbit. Read more “Extortion and Ransomware – A lethal Combination” →

17 Remote Code Execution Vulnerabilities in this month’s patch…

Windows DNS Server

This is really a major issues for Active Directory Domain Controllers.
CVE-2020-1350 : https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1350

We can see there are 2,133 servers on Shodan that are exposed however this exploit doesn’t rely on exposure, a client request from inside the network to a malicious DNS server could be used to exploit the domain controller. Read more “17 Remote Code Execution Vulnerabilities in this month’s patch Tuesday release!” →

Perimeter Security Vendor Hell – Unauthenticated RCE’s and other…

Disclaimer

If your can’t take an honest view on real challegnes we face you probably want to click the back button now!
The three laws of IT apply:

Software has bugs
Hardware breaks
Humans Make Mistakes

It doens’t mean however we shoulnd’t strive to do better! so now that’s out of the way here’s a fast blog on shit you should care about and patch (if you haven’t already!)

Also please note these are not ALL the vulnerabilities you should care about, just some choice ones that are enough to make you cry!

Introduction

“Don’t worry, we’ve got that behind a firewall or VPN!” is something I’ve heard a lot over the years, which to be honest is starting to look more and more worrying. Think that’s just me giving my opinion? Well think again, here we have collated SOME of the vulnerabilities in security products which if unpatched/mitigated really leave you. well quite insecure!

Configuring SYSLOG integration with F5 BIG-IP

CVE-2020-5902 Defensive Guidance (FAST publish)

This week’s been a whirlwind, once again teams of people scrambled to help defend networks from criminals trying to abuse CVE-2020-5902.

If you want to see this in action check out my video on youtube!

The main issue (other than the vulnerability itself (path traversal and unauthenticated remote code execution) is exposing management interfaces to the internet (or other insecure/untrusted networks). Yesterday we looked at IOCs in the “/var/log/audit” file.

Now a sensible attacker who has ROOT level access would have likely cleared their tracks! However, a good sysadmin would have the logs shipped off the device!

Hunting a breach… CVE-2020-5902

I’ve spent the last 24 hours (including a sleeps) gathering intel, testing in the lab and looking at what the path traversal and RCE for the F5 BIG-IP as outlined in CVE-2020-5902 looks like.
Well I’ll be honest.. the whole scenario is a bit of a bloody mess! We’ve got people leaving management interfaces exposed to the internet, we’ve got a vulnerability that’s incredibly old in a security appliance (it’s not exactly uber 1337 either) and we’ve had the release scenario that’s probably ruined peoples weekends and weeks (I’m not going into an Offensive Securitry Tools debate/argument, if you want that go talk to a brick wall or someone else!)