Connect with us

Hi, what are you looking for?

SecurityWeekSecurityWeek

Vulnerabilities

Microsoft Patch Tuesday: Windows Flaw Under Active Attack

The zero-day attacks against Microsoft’s software products continue to pile up with a new warning from Redmond about a zero-day attack hitting a security defect in the Windows Update Medic Service.

The zero-day attacks against Microsoft’s software products continue to pile up with a new warning from Redmond about a zero-day attack hitting a security defect in the Windows Update Medic Service.

The zero-day flaw, documented as CVE-2021-36948, is rated “important” with a CVSS base score of 7.8.

Microsoft described the vulnerability as a local privilege escalation bug, a suggestion that it is part of a larger software exploit chain.

The Windows Update Medic Service is used to repair Windows Update components from damage so that Windows machines can continue to receive software updates. The utility was first introduced in Windows 10 and is an important part of the operating system’s self-healing mechanisms.

This is the 19th documented zero-day attack against Microsoft’s products so far in 2021. Microsoft did not provide any details or indicators of compromise (IOCs) related to this new attack.

[ Related: Microsoft Takes Another Stab at PrintNightmare Security Fix ]

Microsoft’s August batch of security patches also provides cover for multiple code execution flaws in a range of Windows OS and platform components.

In all, Microsoft released patches for 44 documented security vulnerabilities in Windows, Microsoft Office, Windows Defender, WIndows Update, Microsoft Dynamics, and Microsoft Azure.

Advertisement. Scroll to continue reading.

Microsoft said seven of the 44 vulnerabilities are rated “critical” and carry the risk of remote code execution attacks.

The August patches also included cover for a new Windows Print Spooler flaw that Microsoft’s lists as publicly known.   

Separately, Microsoft announced a major default change to the way Windows interacts with the problematic Point and Print driver. Windows will now require admin rights to change the default Point and Print driver installation and update behavior.

This move is meant to be a more comprehensive fix for dangerous security flaws publicly known as PrintNightmare that expose users to remote code execution and privilege escalation attacks.

“Our investigation into several vulnerabilities collectively referred to as “PrintNightmare” has determined that the default behavior of Point and Print does not provide customers with the level of security required to protect against potential attacks,” according to a statement from the Microsoft Security Response Center (MSRC).

[ RelatedDid Microsoft Botch the PrintNightmare Patch? ]

The default change takes effect with the installation of the August batch of security updates for all versions of Windows.   

The PrintNightmare issue has been a public embarrassment for Microsoft as security researchers used social media to highlight major problems with Redmond’s mitigation guidance and the effectiveness of its out-of-band update.

Related: Windows Admins Scrambling to Contain ‘PrintNightmare’ Flaw 

Related: Microsoft Warns of Under-Attack Windows Kernel Flaw

Related: Microsoft Patch Tuesday: 83 Vulnerabilities, 10 Critical, 1 Actively Exploited

Written By

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.

Click to comment

Trending

Daily Briefing Newsletter

Subscribe to the SecurityWeek Email Briefing to stay informed on the latest threats, trends, and technology, along with insightful columns from industry experts.

Join the session as we discuss the challenges and best practices for cybersecurity leaders managing cloud identities.

Register

SecurityWeek’s Ransomware Resilience and Recovery Summit helps businesses to plan, prepare, and recover from a ransomware incident.

Register

Expert Insights

Related Content

Vulnerabilities

Less than a week after announcing that it would suspended service indefinitely due to a conflict with an (at the time) unnamed security researcher...

Data Breaches

OpenAI has confirmed a ChatGPT data breach on the same day a security firm reported seeing the use of a component affected by an...

IoT Security

A group of seven security researchers have discovered numerous vulnerabilities in vehicles from 16 car makers, including bugs that allowed them to control car...

Vulnerabilities

A researcher at IOActive discovered that home security systems from SimpliSafe are plagued by a vulnerability that allows tech savvy burglars to remotely disable...

Risk Management

The supply chain threat is directly linked to attack surface management, but the supply chain must be known and understood before it can be...

Cybercrime

Patch Tuesday: Microsoft calls attention to a series of zero-day remote code execution attacks hitting its Office productivity suite.

Vulnerabilities

Patch Tuesday: Microsoft warns vulnerability (CVE-2023-23397) could lead to exploitation before an email is viewed in the Preview Pane.

Vulnerabilities

The latest Chrome update brings patches for eight vulnerabilities, including seven reported by external researchers.