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Jun 16, 2021
Clop (Cl0p) Ransomware Gang Currently Claims 57 Victims on Leak Site, as Six Clop Gang Members Arrested in Ukraine Today
News broke earlier today that six members of the Clop (CIOp) Ransomware gang were arrested in Kiev, Ukraine and in surrounding towns earlier today by the Cyber Police Department of the National Police of Ukraine, working in cooperation with law enforcement officials from South Korea (the Republic of Korea) and the United States. eSentire’s security research team, the Threat Response Unit (TRU),…
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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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eSentire Revolutionizes Incident Response Services Introducing 4-hour Remote Threat Suppression Globally
Waterloo, ON and Washington, DC – eSentire, recognized globally as the Authority in Managed Detection and Response (MDR), announced today the launch of its Cyber Investigations Portfolio, complete with Emergency Incident Response, Digital Forensics Investigations and Security Incident Response Planning services. Believing that cyber investigations and incident response stand to benefit more from…
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Security advisories — Jun 08, 2021

Microsoft Patch Tuesday – Six Zero-Day Vulnerabilities

3 min read

THE THREAT

On June 8th, Microsoft released security updates to address a total of 50 unique vulnerabilities in their products. These vulnerabilities were disclosed as part of Microsoft’s monthly Patch Tuesday software update. Six vulnerabilities are classified as zero-days, meaning they have been exploited in the wild prior to patch release and are of the most concern. Four of the zero-day vulnerabilities allow for privilege escalation, one allows for information disclosure, and the final vulnerability may be exploited to cause Remote Code Execution (RCE).

Organizations are recommended to immediately prioritize installation of software updates provided by Microsoft to mitigate ongoing activity by threat actors to exploit these zero-day vulnerabilities.

What we’re doing about it

What you should do about it

Additional information

The following vulnerabilities are all reported to have been exploited by threat actors prior to patch release:

CVE-2021-33739 (CVSS: 8.4): Microsoft DWM Core Library Elevation of Privilege Vulnerability

CVE-2021-31956 (CVSS: 7.8): Windows NTFS Elevation of Privilege Vulnerability

CVE-2021-33742 (CVSS: 7.5): Windows MSHTML Platform Remote Code Execution Vulnerability

CVE-2021-31199 (CVSS: 5.2): Microsoft Enhanced Cryptographic Provider Elevation of Privilege Vulnerability

CVE-2021-31201 (CVSS: 5.2): Microsoft Enhanced Cryptographic Provider Elevation of Privilege Vulnerability

CVE-2021-31955 (CVSS: 5.0): Windows Kernel Information Disclosure Vulnerability

CVE-2021-31955 and CVE-2021-31956 were identified and reported to Microsoft by Kaspersky. The company has stated that the vulnerabilities were exploited in highly targeted attacks against multiple organizations. In these attacks, adversaries exploited vulnerabilities in Chrome versions 89.0.4389.128 (patched April 13th) and 90.0.4430.72 (patched April 20th). Additional details on attacks are expected to emerge in the coming days. eSentire continues to investigate these issues for additional details and detection opportunities.

References:

[1] https://msrc.microsoft.com/update-guide
[2] https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-33739
[3] https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-31956
[4] https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-33742
[5] https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-31199
[6] https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-31201
[7] https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-31955
[8] https://securelist.com/puzzlemaker-chrome-zero-day-exploit-chain/102771/