Tag: vulnerability

Defense

Thoughts on IOCs for Exchange Hafnium/ProxyLogon

Intro

This isn’t a rant, far from it but I’ve been working on this for over a week now and some major questions are sprining to mind with regard to how the IOCs and detection details released may have hindered response efforts. These vulnerabilities were known about since at least December 2020, there were months to get detection intel and scripts/tools ready for people (that’s if you don’t question why did it take so long). So I’ve put some of my thoughts down here on some of the challenges with the IoCs initially released and the detection tools etc. I’ll probably update this later but wanted to publish it before it becomes virtual dust! Read more “Thoughts on IOCs for Exchange Hafnium/ProxyLogon”

Defense

Hafnium / Exchange Marauder High Level IR Help

Ok so John and I have been working on this for a while. We have been working with both customers and industry profesionals and there’s a common theme. Understranding the events from this incident are quite challenging because:

  • We don’t have sample log output for known bad traffic
  • The vulns can be used for data theft and/or backdoors (and further actions on target)

Getting guidance out so far on this has been challenging becuase:

  1. There is not a public full kill chain POC to do comaprisons to (i’m ok with that)
  2. We don’t have a pw3d server that has all the indicators from all the routes on

So to try and help people we have made a diagram which we will update as we go.

Essentially you need to perform a weighted analysis to understand if:

  • You had recon only
  • You had some SSRF
  • YOu had SSRF that led to data theft
  • You had a webshell planted
Read more “Hafnium / Exchange Marauder High Level IR Help”
Defense

Checking for Hafnium or other groups impact from Exchange…

Introduction

On March 2nd, 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”

Defense

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.

Read more “vSphere Unauthenticated Remote Code Execution Vulnerability – VMSA-2021-0002”
Defense

Field Notes – Just Patch

Windows update stuck at 0% download status

Often is we find an environment missing software updates it’s easy for someone without hands on experience to say, ‘just patch’. Outside of change requests, outside of authorisation, maintenance windows, roll back plans, communications etc. there is also the fact that ‘just patching’ isn’t that simple. Even for fairly standard patching tasks using Windows Updates you sometimes hit a snag. Today I’m looking at exactly that issue on a server, so I thought I’d post the steps to resolve an issue but also, I think this is a nice way to highlight the realities of patching.

We show a GUI and command line (PowerShell) method to achieve this result (the PowerShell isn’t fancy but I figured you could go away and upgrade that if you fancied some fun). Windows update sometimes has issues (does not all software!) and it is sometimes that we need to help it along the way, so let’s get too it! Read more “Field Notes – Just Patch”

Defense

Vulnerability Management Realities

Trust but verify

Someone tells you they have fixed something, now go and check! You might find that it is not actually fixed, or that the ‘fix’ made the issue worse (or makes new vulnerabilities appear). You might however also find that the vuln is gone.

Wow so many options, but the reality is with this space is that you have to keep checking, you also need to validate.

Validation is key, people do not say that think it is fixed because they have not done something, we all have scenarios where we make a change, assume it works and then find out later that maybe a bit more testing would have helped (I have this too!). Read more “Vulnerability Management Realities”

Defense

Everything must be agile but is that really always…

A lot of people talk about AGILE but the normally mean ‘agile’ however when it comes to security testing and penetration testing (to me there is most certainly a difference) we need to be mindful of the different approaches, so we select the right one for the context, scenario, and objectives.

In this post we take a brief look at what we recommend for a range of scenarios and we look at the key differences and what some constraints might mean when it comes to approach selection.

Read more “Everything must be agile but is that really always the best way?”