Four zero-days vulnerabilities and 71 flaws fixed via this month’s Patch Tuesday

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Updated onOctober 4, 2023

updated onOctober 4, 2023

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Key notes

Today is Microsoft’sOctober 2021 Patch Tuesday, and with it comes fixes for four zero-day vulnerabilities and a total of 74 flaws.

Microsoft has fixed 74 vulnerabilities (81 including Microsoft Edge) with today’s update, with three classified as Critical, and 70 as Important, and one as Low.

4 zero-days vulnerabilities fixed, with one actively exploited

These 81 vulnerabilities that are being patched during this month’s rollout are split into categories, as follows:

October’s Patch Tuesday includes fixes for four zero-day vulnerabilities, with a Win32k Elevation of Privilege Vulnerability vulnerability known to have been actively exploited in attacks.

Microsoft classifies a vulnerability as a zero-day if it is publicly disclosed or actively exploited with no official fix available.

The actively exploited vulnerability was discovered by Kaspersky’s Boris Larin (oct0xor) and allows malware or a threat actor to gain elevated privileges on a Windows device.

IronHusky APT uses zero-day on Windows servers#MysterySnail#PatchTuesday#itw0dayshttps://t.co/QnhtJyNfdD

Kasperskydisclosedthat the vulnerability was used by threat actors in “widespread espionage campaigns against IT companies, military/defense contractors, and diplomatic entities.”

As part of the attacks, the threat actors installed a remote access trojan (RAT) that was elevated with higher permissions using the zero-day Windows vulnerability.

Thus, Kaspersky calls this cluster of malicious activity MysterSnail and is attributed to the IronHusky and Chinese-speaking APT activity.

Microsoft also fixed three other publicly disclosed vulnerabilities that are not known to be exploited in attacks.

Other companies also released important updates

This month’s security updates

Below is the complete list of resolved vulnerabilities and released advisories in the October 2021 Patch Tuesday updates. To access the full description of each vulnerability and the systems that it affects, you can view thefull report here.

Have you been struggling with any of the errors and bugs listed in this article? Let us know in the comments section below.

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Four zero-days vulnerabilities and 71 flaws fixed via this month’s Patch Tuesday#

4 zero-days vulnerabilities fixed, with one actively exploited#

Other companies also released important updates#

This month’s security updates#

With KB5043178 to Release Preview Channel, Microsoft advises Windows 11 users to plug in when the battery is low

Copilot in Outlook will generate personalized themes for you to customize the app

Microsoft will raise the price of its 365 Suite to include AI capabilities

Death Stranding Director’s Cut is now Xbox X|S at a huge discount

Outlook will let users create custom account icons so they can tell their accounts apart easier

Four zero-days vulnerabilities and 71 flaws fixed via this month’s Patch Tuesday

4 zero-days vulnerabilities fixed, with one actively exploited

Other companies also released important updates

This month’s security updates