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Jul 29, 2021
UPDATE: PetitPotam NTLM Relay Attack
THE THREAT PetitPotam is a variant of the NTLM Relay attack discovered by security researcher Gilles Lionel. It is tracked as an authentication bypass vulnerability in Active Directory (Certificate Services); currently no CVE identifier has been assigned to this vulnerability. Proof of Concept (PoC) code released last week [1] relies on the Encrypting File System Remote (EFSRPC) protocol to…
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eSentire is The Authority in Managed Detection and Response Services, protecting the critical data and applications of 1000+ organizations in 70+ countries from known and unknown cyber threats. Founded in 2001, the company’s mission is to hunt, investigate and stop cyber threats before they become business disrupting events.
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Tecala and eSentire Partner to Protect Enterprises across APAC from Business-Disrupting Cyber Attacks
Sydney, 12 July, 2021 - Tecala, Australia’s award-winning technology services and IT consulting provider, today announced it has chosen eSentire, the global Authority in Managed Detection and Response (MDR) cybersecurity services, as their exclusive MDR solution provider in Australia and New Zealand. This partnership will enable Tecala to augment its cybersecurity practice and offer enterprises…
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Security advisories — Mar 08, 2021

Update 2: Multiple 0-Day Exploits Targeting on Premise Exchange Versions

3 min read

THE THREAT

In response to the ongoing exploitation of recently disclosed Microsoft Exchange server zero-day vulnerabilities, Microsoft has released new mitigations for organizations that are currently unable to apply the required security patches. Importantly, Microsoft has also released the Microsoft Support Emergency Response Tool (MSERT). The MSERT tool can be used to detect and remediate known threats abusing these vulnerabilities.

Organizations are strongly recommended to ensure that security patches or mitigations are deployed to prevent exploitation. The MSERT tool should be used to help identify potentially malicious actions that may have occurred prior to patch or mitigation deployment.

What we’re doing about it

What you should do about it

Additional information

Confirmed vulnerable on-premises Microsoft Exchange Servers:

Exploited Vulnerabilities:

Microsoft has provided mitigations to defend against attacks exploiting all of the previously stated vulnerabilities. It should be noted that applying the mitigation actions will result in functionality degradation in Exchange servers. The functionality impact of each mitigation action is outline in detail in the official release. Microsoft has released a free Nmap script to scan for CVE-2021-26855.

References:

[1] https://msrc.microsoft.com/update-guide/releaseNote/2021-Mar

[2] https://msrc-blog.microsoft.com/2021/03/05/microsoft-exchange-server-vulnerabilities-mitigations-march-2021/

[3] https://docs.microsoft.com/en-us/windows/security/threat-protection/intelligence/safety-scanner-download

[4] https://github.com/microsoft/CSS-Exchange/blob/main/Security/http-vuln-cve2021-26855.nse