Chinese Hafnium Group Probably PWNED Your Exchange Server - Ticking Time Bomb Doubling Every Two Hours!

Discuss it here. This is starting to feel like WannaCry:{
Update: According to Check Point Research (CPR), threat actors are actively exploiting four zero-day vulnerabilities tackled with emergency fixes issued by Microsoft on March 2 – and attack attempts continue to rise. In the past 24 hours, the team has observed “exploitation attempts on organizations doubling every two to three hours.”

In addition to data theft potential threats might also include hijacked email threads, spear phishing, ransomware, and social engineering attempts.Highly recommended to keep your employees on high alert!

The countries feeling the brunt of attack attempts are Turkey, the United States, and Italy, accounting for 19%, 18%, and 10% of all tracked exploit attempts, respectively.

Some seriously bad news for hundreds of thousands of businesses running Microsoft Exchange
Servers around the world attributed to the Chinese hacking group called “Hafnium” who exploited a zero-day attack on Exchange servers versions 2013 through 2019. It was initially believed to have affected at least 30,000 servers in the US but that number may be much much higher, compromising perhaps a hundreds thousand or more Exchange servers around the world. This exploit hit both small and large businesses/organizations, local, state, and federal government entities. Microsoft released out of band patches this Tuesday as well as offering a scripting tool to help determine if Exchange servers were compromised. ESET says at least 10 APT groups are piling on. It’s likely more may follow the herd.

According to Brian Krebs,“each hacked server has been retrofitted with a “web shell” backdoor that gives the bad guys total, remote control, the ability to read all email, and easy access to the victim’s other computers. Researchers are now racing to identify, alert and help victims, and hopefully prevent further mayhem.”

The problems is so bad that the Biden administration issued an emergency task force to assess all federal government servers immediately. As Brian Krebs wrote, "The truth is, if you are running an OWA server exposed to the internet, assume you have been compromised between 02/26-03/03 and you are now in incident response mode until proven otherwise. Typically the Chinese main goal was espionage and attainment of intellectual property. Yet it’s unclear at this point what the end game is.
According to ZDNET, Mandiant says further attacks against US targets include local government bodies, a university, an engineering company, and retailers. The cyberforensics firm believes the vulnerabilities could be used for the purposes of ransomware deployment and data theft.

On Saturday, the US Cybersecurity and Infrastructure Security Agency (CISA) encouraged all organizations using Exchange to scan devices for vulnerabilities. The White House press secretary, Jen Psaki, told the press in a briefing on Friday." The breach represents “a significant vulnerability that could have far-reaching impacts This is an active threat. “We are concerned that there are a large number of victims and are working with our partners to understand the scope of this”

Microsoft’s Incident Response Explanation And Detection Script

CISA ALERT - Mitigate Microsoft Exchange Server Vulnerabilities

Microsoft announced in their blog today they are releasing a mitigation tool for customers who don’t have a dedicated security team to apply the recommended patches and is meant as a temporary solution and may not protect against all future attacks.

Microsoft has released a new, one-click mitigation tool, Microsoft Exchange On-Premises Mitigation Tool to help customers who do not have dedicated security or IT teams to apply these security updates.* We have tested this tool across Exchange Server 2013, 2016, and 2019 deployments. This new tool is designed as an interim mitigation for customers who are unfamiliar with the patch/update process or who have not yet applied the on-premises Exchange security update.


Before running the tool, you should understand:

  • The Exchange On-premises Mitigation Tool is effective against the attacks we have seen so far, but is not guaranteed to mitigate all possible future attack techniques. This tool should only be used as a temporary mitigation until your Exchange servers can be fully updated as outlined in our previous guidance.
  • We recommend this script over the previous ExchangeMitigations.ps1 script as it tuned based on the latest threat intelligence. If you have already started with the other script, it is fine to switch to this one.
  • This is a recommended approach for Exchange deployments with Internet access and for those who want to attempt automated remediation.
  • Thus far, we have not observed any impact to Exchange Server functionality when these mitigation methods are deployed.

Privacy Policy | Terms of Service