Defense

Exchange Emergency Mitigation Service with new CU Update

This is a big thing in the Exchange world from my POV! I believe this is dropping sometime today (28th September!)

History

Exchange OWA, ECP etc. are exposed online not only for mailbox access, calendar sharing but also are a requirement for hybrid mode sync capabilities.

Vulnerabilities in Exchange this year (ProxyLogon/ProxyShell) have shown how problematic an attack surface this is. The good news is, Microsoft have created a feature for Exchange to help mitigate these attacks in the future via the EM Service!

Read more “Exchange Emergency Mitigation Service with new CU Update”
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”