Uncategorized

Microsoft Issues Emergency Patch as Chinese Hackers Exploiting Exchange Server Flaws

The Microsoft Security Response Center yesterday released several security updates for Microsoft Exchange Server. These updates were targeted at addressing vulnerabilities that have been used in a few focused and targeted attacks.

Nature of vulnerabilities

The vulnerabilities have been deemed to be very critical in nature and Microsoft urges and advises its customers to update the affected systems without further delay to protect themselves against these attacks and to prevent further abuse of their systems.

Microsoft states that these vulnerabilities have affected only Microsoft Exchange Server and have not affected Exchange Online.

Vulnerabilities

Affected versions

  • Microsoft Exchange Server 2013
  • Microsoft Exchange Server 2016
  • Microsoft Exchange Server 2019

Defense in Depth purpose updates is being carried out on Microsoft Exchange Server 2010.

HAFNIUM Targeting Exchange Servers

“Microsoft has detected multiple 0-day exploits being used to attack on-premises versions of Microsoft Exchange Server in limited and targeted attacks. In the attacks observed, the threat actor used these vulnerabilities to access on-premises Exchange servers which enabled access to email accounts, and allowed the installation of additional malware to facilitate long-term access to victim environments.”

Process and mitigating ways of vulnerabilities

The vulnerabilities were used as part of an attack chain. Initially, these attacks need to have the ability to make an untrusted connection to Exchange server port 443 which can be saved by either restricting the untrusted connections, or by setting up a VPN to separate the Exchange server from external access.

By using this proposed method of protection, one would only protect against the initial portion of the attack. But other portions of the chain can be triggered if an attacker already has access or can convince an administrator to run a malicious file.

Microsoft has asked its users to prioritize updating external-facing Exchange Servers and then moving on to update others.

You can follow us on LinkedinTwitterFacebook for daily Cybersecurity, and hacking news updates.

Gurubaran

Gurubaran is a co-founder of Cyber Security News and GBHackers On Security. He has 10+ years of experience as a Security Consultant, Editor, and Analyst in cybersecurity, technology, and communications.

Recent Posts

Threat Actors Manipulate Search Results to Lure Users to Malicious Websites

Cybercriminals are increasingly exploiting search engine optimization (SEO) techniques and paid advertisements to manipulate search…

18 hours ago

Hackers Imitate Google Chrome Install Page on Google Play to Distribute Android Malware

Cybersecurity experts have unearthed an intricate cyber campaign that leverages deceptive websites posing as the…

18 hours ago

Dangling DNS Attack Allows Hackers to Take Over Organization’s Subdomain

Hackers are exploiting what's known as "Dangling DNS" records to take over corporate subdomains, posing…

18 hours ago

HelloKitty Ransomware Returns, Launching Attacks on Windows, Linux, and ESXi Environments

Security researchers and cybersecurity experts have recently uncovered new variants of the notorious HelloKitty ransomware,…

18 hours ago

RansomHub Ransomware Group Hits 84 Organizations as New Threat Actors Emerge

The RansomHub ransomware group has emerged as a significant danger, targeting a wide array of…

19 hours ago

Threat Actors Leverage Email Bombing to Evade Security Tools and Conceal Malicious Activity

Threat actors are increasingly using email bombing to bypass security protocols and facilitate further malicious…

1 day ago