It’s raining patches in the Microsoft Windows ecosystem.
The Redmond, Wash. software giant on Tuesday dropped a mega-batch of security updates with patches for a whopping 89 documented vulnerabilities, including one used in zero-day attacks against some in the white-hat hacker community.
This month’s Patch Tuesday whopper comes just one week after Microsoft scrambled out emergency fixes to provide cover for in-the-wild nation-state attacks targeting Exchange Server installations.
Microsoft has blamed those attacks on Chinese cyber-espionage actors operating from leased VPS (virtual private servers) in the United States. The APT group has hit tens of thousands of organizations around the world, including targeted sectors like defense contractors, policy think tanks, and NGOs.
[ ALSO SEE: Multiple Exchange Server Zero-Days Under Attack ]
Microsoft also provided cover for a separate Internet Explorer vulnerability (CVE-2021-26411) that was used by North Korean government-backed hackers to target security researchers in South Korea.
The IE zero-day (Internet Explorer, interestingly, remains widely deployed in South Korea, was flagged by security vendor ENKI in February alongside a warning about drive-by browser IE downloads. Security researchers at Kaspersky have linked the attacks to a sub-group under Lazarus, the infamous North Korean threat actor known for launching destructive malware and ransomware attacks across the globe.
[ ALSO SEE: Google Chrome, Microsoft IE Zero-Days in Crosshairs ]
In all, Microsoft documented 89 distinct vulnerabilities across a range of software and cloud-delivered products in its portfolio. The patches cover serious flaws in multiple Windows OS components, Office and Office Services and Web Apps, SharePoint Server, Visual Studio, Azure and Azure Sphere.
Microsoft slapped a critical rating on 14 of the 89 documented vulnerabilities, while 75 carry an “important” severity rating.
According to Microsoft, two of these bugs are listed as publicly known while five are listed as under active attack at the time of release.
As usual, TippingPoint ZDI has a comprehensive wrap-up of this month’s Microsoft patch release.
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Ryan Naraine is Editor-at-Large at SecurityWeek and host of the popular Security Conversations podcast series. He is a security community engagement expert who has built programs at major global brands, including Intel Corp., Bishop Fox and GReAT. Ryan is a founding-director of the Security Tinkerers non-profit, an advisor to early-stage entrepreneurs, and a regular speaker at security conferences around the world.
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