Microsoft Releases Updates to Patch Critical Flaws in Windows and Other Software

Microsoft has rolled out fixes for its Windows operating system and other software components to remediate major security shortcomings as part of Patch Tuesday updates for June 2023. Of the 73 flaws, six are rated Critical, 63 are rated Important, two are rated Moderate, and one is rated Low in severity. This also includes three issues the tech giant addressed in its Chromium-based Edge browser.

Chinese Hackers Exploit VMware Zero-Day to Backdoor Windows and Linux Systems

The Chinese state-sponsored group known as UNC3886 has been found to exploit a zero-day flaw in VMware ESXi hosts to backdoor Windows and Linux systems. The VMware Tools authentication bypass vulnerability, tracked as CVE-2023-20867 (CVSS score: 3.9), "enabled the execution of privileged commands across Windows, Linux, and PhotonOS (vCenter) guest VMs without authentication of guest credentials

Iranian Hackers' Sophisticated Malware Targets Windows and macOS Users

The Iranian nation-state actor known as TA453 has been linked to a new set of spear-phishing attacks that infect both Windows and macOS operating systems with malware. "TA453 eventually used a variety of cloud hosting providers to deliver a novel infection chain that deploys the newly identified PowerShell backdoor GorjolEcho," Proofpoint said in a new report. "When given the opportunity, TA453

Microsoft Releases Patches for 132 Vulnerabilities, Including 6 Under Active Attack

Microsoft on Tuesday released updates to address a total of 132 new security flaws spanning its software, including six zero-day flaws that it said have been actively exploited in the wild. Of the 132 vulnerabilities, nine are rated Critical, 122 are rated Important in severity, and one has been assigned a severity rating of "None." This is in addition to eight flaws the tech giant patched in

Experts Uncover Weaknesses in PowerShell Gallery Enabling Supply Chain Attacks

Active flaws in the PowerShell Gallery could be weaponized by threat actors to pull off supply chain attacks against the registry's users. "These flaws make typosquatting attacks inevitable in this registry, while also making it extremely difficult for users to identify the true owner of a package," Aqua security researchers Mor Weinberger, Yakir Kadkoda, and Ilay Goldman said in a report shared

This Malware Turned Thousands of Hacked Windows and macOS PCs into Proxy Servers

Threat actors are leveraging access to malware-infected Windows and macOS machines to deliver a proxy server application and use them as exit nodes to reroute proxy requests. According to AT&T Alien Labs, the unnamed company that offers the proxy service operates more than 400,000 proxy exit nodes, although it's not immediately clear how many of them were co-opted by malware installed on

Hackers Can Exploit Windows Container Isolation Framework to Bypass Endpoint Security

New findings show that malicious actors could leverage a sneaky malware detection evasion technique and bypass endpoint security solutions by manipulating the Windows Container Isolation Framework. The findings were presented by Deep Instinct security researcher Daniel Avinoam at the DEF CON security conference held earlier this month. Microsoft's container architecture (and by extension, 

Cybercriminals Weaponizing Legitimate Advanced Installer Tool in Crypto-Mining Attacks

A legitimate Windows tool used for creating software packages called Advanced Installer is being abused by threat actors to drop cryptocurrency-mining malware on infected machines since at least November 2021. "The attacker uses Advanced Installer to package other legitimate software installers, such as Adobe Illustrator, Autodesk 3ds Max, and SketchUp Pro, with malicious scripts and uses

Alert: New Kubernetes Vulnerabilities Enable Remote Attacks on Windows Endpoints

Three interrelated high-severity security flaws discovered in Kubernetes could be exploited to achieve remote code execution with elevated privileges on Windows endpoints within a cluster. The issues, tracked as CVE-2023-3676, CVE-2023-3893, and CVE-2023-3955, carry CVSS scores of 8.8 and impact all Kubernetes environments with Windows nodes. Fixes for the vulnerabilities were released on August

Microsoft is Rolling out Support for Passkeys in Windows 11

Microsoft is officially rolling out support for passkeys in Windows 11 today as part of a major update to the desktop operating system. The feature allows users to login to websites and applications without having to provide a username and password, instead relying on their device PIN or biometric information to complete the step. Based on FIDO standards, Passkeys were first announced in May

Patch Tuesday, October 2023 Edition

Microsoft today issued security updates for more than 100 newly-discovered vulnerabilities in its Windows operating system and related software, including four flaws that are already being exploited. In addition, Apple recently released emergency updates to quash a pair of zero-day bugs in iOS.

Apple last week shipped emergency updates in iOS 17.0.3 and iPadOS 17.0.3 in response to active attacks. The patch fixes CVE-2023-42724, which attackers have been using in targeted attacks to elevate their access on a local device.

Apple said it also patched CVE-2023-5217, which is not listed as a zero-day bug. However, as Bleeping Computer pointed out, this flaw is caused by a weakness in the open-source “libvpx” video codec library, which was previously patched as a zero-day flaw by Google in the Chrome browser and by Microsoft in Edge, Teams, and Skype products. For anyone keeping count, this is the 17th zero-day flaw that Apple has patched so far this year.

Fortunately, the zero-days affecting Microsoft customers this month are somewhat less severe than usual, with the exception of CVE-2023-44487. This weakness is not specific to Windows but instead exists within the HTTP/2 protocol used by the World Wide Web: Attackers have figured out how to use a feature of HTTP/2 to massively increase the size of distributed denial-of-service (DDoS) attacks, and these monster attacks reportedly have been going on for several weeks now.

Amazon, Cloudflare and Google all released advisories today about how they’re addressing CVE-2023-44487 in their cloud environments. Google’s Damian Menscher wrote on Twitter/X that the exploit — dubbed a “rapid reset attack” — works by sending a request and then immediately cancelling it (a feature of HTTP/2). “This lets attackers skip waiting for responses, resulting in a more efficient attack,” Menscher explained.

Natalie Silva, lead security engineer at Immersive Labs, said this flaw’s impact to enterprise customers could be significant, and lead to prolonged downtime.

“It is crucial for organizations to apply the latest patches and updates from their web server vendors to mitigate this vulnerability and protect against such attacks,” Silva said. In this month’s Patch Tuesday release by Microsoft, they have released both an update to this vulnerability, as well as a temporary workaround should you not be able to patch immediately.”

Microsoft also patched zero-day bugs in Skype for Business (CVE-2023-41763) and Wordpad (CVE-2023-36563). The latter vulnerability could expose NTLM hashes, which are used for authentication in Windows environments.

“It may or may not be a coincidence that Microsoft announced last month that WordPad is no longer being updated, and will be removed in a future version of Windows, although no specific timeline has yet been given,” said Adam Barnett, lead software engineer at Rapid7. “Unsurprisingly, Microsoft recommends Word as a replacement for WordPad.”

Other notable bugs addressed by Microsoft include CVE-2023-35349, a remote code execution weakness in the Message Queuing (MSMQ) service, a technology that allows applications across multiple servers or hosts to communicate with each other. This vulnerability has earned a CVSS severity score of 9.8 (10 is the worst possible). Happily, the MSMQ service is not enabled by default in Windows, although Immersive Labs notes that Microsoft Exchange Server can enable this service during installation.

Speaking of Exchange, Microsoft also patched CVE-2023-36778,  a vulnerability in all current versions of Exchange Server that could allow attackers to run code of their choosing. Rapid7’s Barnett said successful exploitation requires that the attacker be on the same network as the Exchange Server host, and use valid credentials for an Exchange user in a PowerShell session.

For a more detailed breakdown on the updates released today, see the SANS Internet Storm Center roundup. If today’s updates cause any stability or usability issues in Windows, AskWoody.com will likely have the lowdown on that.

Please consider backing up your data and/or imaging your system before applying any updates. And feel free to sound off in the comments if you experience any difficulties as a result of these patches.

Microsoft Releases October 2023 Patches for 103 Flaws, Including 2 Active Exploits

Microsoft has released its Patch Tuesday updates for October 2023, addressing a total of 103 flaws in its software, two of which have come under active exploitation in the wild. Of the 103 flaws, 13 are rated Critical and 90 are rated Important in severity. This is apart from 18 security vulnerabilities addressed in its Chromium-based Edge browser since the second Tuesday of September. The two

Microsoft to Phase Out NTLM in Favor of Kerberos for Stronger Authentication

Microsoft has announced that it plans to eliminate NT LAN Manager (NTLM) in Windows 11 in the future, as it pivots to alternative methods for authentication and bolster security. "The focus is on strengthening the Kerberos authentication protocol, which has been the default since 2000, and reducing reliance on NT LAN Manager (NTLM)," the tech giant said. "New features for Windows 11 include

Hackers Using MSIX App Packages to Infect Windows PCs with GHOSTPULSE Malware

A new cyber attack campaign has been observed using spurious MSIX Windows app package files for popular software such as Google Chrome, Microsoft Edge, Brave, Grammarly, and Cisco Webex to distribute a novel malware loader dubbed GHOSTPULSE. "MSIX is a Windows app package format that developers can leverage to package, distribute, and install their applications to Windows users," Elastic

Researchers Find 34 Windows Drivers Vulnerable to Full Device Takeover

As many as 34 unique vulnerable Windows Driver Model (WDM) and Windows Driver Frameworks (WDF) drivers could be exploited by non-privileged threat actors to gain full control of the devices and execute arbitrary code on the underlying systems. "By exploiting the drivers, an attacker without privilege may erase/alter firmware, and/or elevate [operating system] privileges," Takahiro Haruyama, a

New Flaws in Fingerprint Sensors Let Attackers Bypass Windows Hello Login

A new research has uncovered multiple vulnerabilities that could be exploited to bypass Windows Hello authentication on Dell Inspiron 15, Lenovo ThinkPad T14, and Microsoft Surface Pro X laptops. The flaws were discovered by researchers at hardware and software product security and offensive research firm Blackwing Intelligence, who found the weaknesses in the fingerprint sensors from Goodix,

Beware: Experts Reveal New Details on Zero-Click Outlook RCE Exploits

Technical details have emerged about two now-patched security flaws in Microsoft Windows that could be chained by threat actors to achieve remote code execution on the Outlook email service sans any user interaction. "An attacker on the internet can chain the vulnerabilities together to create a full, zero-click remote code execution (RCE) exploit against Outlook clients," Akamai security

New Variant of DLL Search Order Hijacking Bypasses Windows 10 and 11 Protections

Security researchers have detailed a new variant of a dynamic link library (DLL) search order hijacking technique that could be used by threat actors to bypass security mechanisms and achieve execution of malicious code on systems running Microsoft Windows 10 and Windows 11. The approach "leverages executables commonly found in the trusted WinSxS folder and exploits them via the classic DLL

New Bandook RAT Variant Resurfaces, Targeting Windows Machines

A new variant of a remote access trojan called Bandook has been observed being propagated via phishing attacks with an aim to infiltrate Windows machines, underscoring the continuous evolution of the malware. Fortinet FortiGuard Labs, which identified the activity in October 2023, said the malware is distributed via a PDF file that embeds a link to a password-protected .7z archive. “

Microsoft's January 2024 Windows Update Patches 48 New Vulnerabilities

Microsoft has addressed a total of 48 security flaws spanning its software as part of its Patch Tuesday updates for January 2024. Of the 48 bugs, two are rated Critical and 46 are rated Important in severity. There is no evidence that any of the issues are publicly known or under active attack at the time of release, making it the second consecutive Patch Tuesday with no zero-days. The

Hackers Weaponize Windows Flaw to Deploy Crypto-Siphoning Phemedrone Stealer

Threat actors have been observed leveraging a now-patched security flaw in Microsoft Windows to deploy an open-source information stealer called Phemedrone Stealer. “Phemedrone targets web browsers and data from cryptocurrency wallets and messaging apps such as Telegram, Steam, and Discord,” Trend Micro researchers Peter Girnus, Aliakbar Zahravi, and Simon Zuckerbraun said. “It also

Researchers Uncover How Outlook Vulnerability Could Leak Your NTLM Passwords

A now-patched security flaw in Microsoft Outlook could be exploited by threat actors to access NT LAN Manager (NTLM) v2 hashed passwords when opening a specially crafted file. The issue, tracked as CVE-2023-35636 (CVSS score: 6.5), was addressed by the tech giant as part of its Patch Tuesday updates for December 2023. "In an email attack scenario, an attacker could exploit the

DirtyMoe Malware Infects 2,000+ Ukrainian Computers for DDoS and Cryptojacking

The Computer Emergency Response Team of Ukraine (CERT-UA) has warned that more than 2,000 computers in the country have been infected by a strain of malware called DirtyMoe. The agency attributed the campaign to a threat actor it calls UAC-0027. DirtyMoe, active since at least 2016, is capable of carrying out cryptojacking and distributed denial-of-service (DDoS) attacks. In March

Microsoft Introduces Linux-Like 'sudo' Command to Windows 11

Microsoft said it's introducing Sudo for Windows 11 as part of an early preview version to help users execute commands with administrator privileges. "Sudo for Windows is a new way for users to run elevated commands directly from an unelevated console session," Microsoft Product Manager Jordi Adoumie said. "It is an ergonomic and familiar solution for users who want to elevate a command

Fat Patch Tuesday, February 2024 Edition

Microsoft Corp. today pushed software updates to plug more than 70 security holes in its Windows operating systems and related products, including two zero-day vulnerabilities that are already being exploited in active attacks.

Top of the heap on this Fat Patch Tuesday is CVE-2024-21412, a “security feature bypass” in the way Windows handles Internet Shortcut Files that Microsoft says is being targeted in active exploits. Redmond’s advisory for this bug says an attacker would need to convince or trick a user into opening a malicious shortcut file.

Researchers at Trend Micro have tied the ongoing exploitation of CVE-2024-21412 to an advanced persistent threat group dubbed “Water Hydra,” which they say has being using the vulnerability to execute a malicious Microsoft Installer File (.msi) that in turn unloads a remote access trojan (RAT) onto infected Windows systems.

The other zero-day flaw is CVE-2024-21351, another security feature bypass — this one in the built-in Windows SmartScreen component that tries to screen out potentially malicious files downloaded from the Web. Kevin Breen at Immersive Labs says it’s important to note that this vulnerability alone is not enough for an attacker to compromise a user’s workstation, and instead would likely be used in conjunction with something like a spear phishing attack that delivers a malicious file.

Satnam Narang, senior staff research engineer at Tenable, said this is the fifth vulnerability in Windows SmartScreen patched since 2022 and all five have been exploited in the wild as zero-days. They include CVE-2022-44698 in December 2022, CVE-2023-24880 in March 2023, CVE-2023-32049 in July 2023 and CVE-2023-36025 in November 2023.

Narang called special attention to CVE-2024-21410, an “elevation of privilege” bug in Microsoft Exchange Server that Microsoft says is likely to be exploited by attackers. Attacks on this flaw would lead to the disclosure of NTLM hashes, which could be leveraged as part of an NTLM relay or “pass the hash” attack, which lets an attacker masquerade as a legitimate user without ever having to log in.

“We know that flaws that can disclose sensitive information like NTLM hashes are very valuable to attackers,” Narang said. “A Russian-based threat actor leveraged a similar vulnerability to carry out attacks – CVE-2023-23397 is an Elevation of Privilege vulnerability in Microsoft Outlook patched in March 2023.”

Microsoft notes that prior to its Exchange Server 2019 Cumulative Update 14 (CU14), a security feature called Extended Protection for Authentication (EPA), which provides NTLM credential relay protections, was not enabled by default.

“Going forward, CU14 enables this by default on Exchange servers, which is why it is important to upgrade,” Narang said.

Rapid7’s lead software engineer Adam Barnett highlighted CVE-2024-21413, a critical remote code execution bug in Microsoft Office that could be exploited just by viewing a specially-crafted message in the Outlook Preview pane.

“Microsoft Office typically shields users from a variety of attacks by opening files with Mark of the Web in Protected View, which means Office will render the document without fetching potentially malicious external resources,” Barnett said. “CVE-2024-21413 is a critical RCE vulnerability in Office which allows an attacker to cause a file to open in editing mode as though the user had agreed to trust the file.”

Barnett stressed that administrators responsible for Office 2016 installations who apply patches outside of Microsoft Update should note the advisory lists no fewer than five separate patches which must be installed to achieve remediation of CVE-2024-21413; individual update knowledge base (KB) articles further note that partially-patched Office installations will be blocked from starting until the correct combination of patches has been installed.

It’s a good idea for Windows end-users to stay current with security updates from Microsoft, which can quickly pile up otherwise. That doesn’t mean you have to install them on Patch Tuesday. Indeed, waiting a day or three before updating is a sane response, given that sometimes updates go awry and usually within a few days Microsoft has fixed any issues with its patches. It’s also smart to back up your data and/or image your Windows drive before applying new updates.

For a more detailed breakdown of the individual flaws addressed by Microsoft today, check out the SANS Internet Storm Center’s list. For those admins responsible for maintaining larger Windows environments, it often pays to keep an eye on Askwoody.com, which frequently points out when specific Microsoft updates are creating problems for a number of users.

April’s Patch Tuesday Brings Record Number of Fixes

If only Patch Tuesdays came around infrequently — like total solar eclipse rare — instead of just creeping up on us each month like The Man in the Moon. Although to be fair, it would be tough for Microsoft to eclipse the number of vulnerabilities fixed in this month’s patch batch — a record 147 flaws in Windows and related software.

Yes, you read that right. Microsoft today released updates to address 147 security holes in Windows, Office, Azure, .NET Framework, Visual Studio, SQL Server, DNS Server, Windows Defender, Bitlocker, and Windows Secure Boot.

“This is the largest release from Microsoft this year and the largest since at least 2017,” said Dustin Childs, from Trend Micro’s Zero Day Initiative (ZDI). “As far as I can tell, it’s the largest Patch Tuesday release from Microsoft of all time.”

Tempering the sheer volume of this month’s patches is the middling severity of many of the bugs. Only three of April’s vulnerabilities earned Microsoft’s most-dire “critical” rating, meaning they can be abused by malware or malcontents to take remote control over unpatched systems with no help from users.

Most of the flaws that Microsoft deems “more likely to be exploited” this month are marked as “important,” which usually involve bugs that require a bit more user interaction (social engineering) but which nevertheless can result in system security bypass, compromise, and the theft of critical assets.

Ben McCarthy, lead cyber security engineer at Immersive Labs called attention to CVE-2024-20670, an Outlook for Windows spoofing vulnerability described as being easy to exploit. It involves convincing a user to click on a malicious link in an email, which can then steal the user’s password hash and authenticate as the user in another Microsoft service.

Another interesting bug McCarthy pointed to is CVE-2024-29063, which involves hard-coded credentials in Azure’s search backend infrastructure that could be gleaned by taking advantage of Azure AI search.

“This along with many other AI attacks in recent news shows a potential new attack surface that we are just learning how to mitigate against,” McCarthy said. “Microsoft has updated their backend and notified any customers who have been affected by the credential leakage.”

CVE-2024-29988 is a weakness that allows attackers to bypass Windows SmartScreen, a technology Microsoft designed to provide additional protections for end users against phishing and malware attacks. Childs said one of ZDI’s researchers found this vulnerability being exploited in the wild, although Microsoft doesn’t currently list CVE-2024-29988 as being exploited.

“I would treat this as in the wild until Microsoft clarifies,” Childs said. “The bug itself acts much like CVE-2024-21412 – a [zero-day threat from February] that bypassed the Mark of the Web feature and allows malware to execute on a target system. Threat actors are sending exploits in a zipped file to evade EDR/NDR detection and then using this bug (and others) to bypass Mark of the Web.”

Update, 7:46 p.m. ET: A previous version of this story said there were no zero-day vulnerabilities fixed this month. BleepingComputer reports that Microsoft has since confirmed that there are actually two zero-days. One is the flaw Childs just mentioned (CVE-2024-21412), and the other is CVE-2024-26234, described as a “proxy driver spoofing” weakness.

Satnam Narang at Tenable notes that this month’s release includes fixes for two dozen flaws in Windows Secure Boot, the majority of which are considered “Exploitation Less Likely” according to Microsoft.

“However, the last time Microsoft patched a flaw in Windows Secure Boot in May 2023 had a notable impact as it was exploited in the wild and linked to the BlackLotus UEFI bootkit, which was sold on dark web forums for $5,000,” Narang said. “BlackLotus can bypass functionality called secure boot, which is designed to block malware from being able to load when booting up. While none of these Secure Boot vulnerabilities addressed this month were exploited in the wild, they serve as a reminder that flaws in Secure Boot persist, and we could see more malicious activity related to Secure Boot in the future.”

For links to individual security advisories indexed by severity, check out ZDI’s blog and the Patch Tuesday post from the SANS Internet Storm Center. Please consider backing up your data or your drive before updating, and drop a note in the comments here if you experience any issues applying these fixes.

Adobe today released nine patches tackling at least two dozen vulnerabilities in a range of software products, including Adobe After Effects, Photoshop, Commerce, InDesign, Experience Manager, Media Encoder, Bridge, Illustrator, and Adobe Animate.

KrebsOnSecurity needs to correct the record on a point mentioned at the end of March’s “Fat Patch Tuesday” post, which looked at new AI capabilities built into Adobe Acrobat that are turned on by default. Adobe has since clarified that its apps won’t use AI to auto-scan your documents, as the original language in its FAQ suggested.

“In practice, no document scanning or analysis occurs unless a user actively engages with the AI features by agreeing to the terms, opening a document, and selecting the AI Assistant or generative summary buttons for that specific document,” Adobe said earlier this month.