Qualys

Microsoft Patch Tuesday, March 2020 Edition

Microsoft Corp. today released updates to plug more than 100 security holes in its various Windows operating systems and associated software. If you (ab)use Windows, please take a moment to read this post, backup your system(s), and patch your PCs.

All told, this patch batch addresses at least 115 security flaws. Twenty-six of those earned Microsoft’s most-dire “critical” rating, meaning malware or miscreants could exploit them to gain complete, remote control over vulnerable computers without any help from users.

Given the sheer number of fixes, mercifully there are no zero-day bugs to address, nor were any of them detailed publicly prior to today. Also, there were no security patches released by Adobe today. But there are a few eyebrow-raising Windows vulnerabilities worthy of attention.

Recorded Future warns exploit code is now available for one of the critical bugs Redmond patched last month in Microsoft Exchange (CVE-2020-0688), and that nation state actors have been observed abusing the exploit for targeted attacks.

One flaw fixed this month in Microsoft Word (CVE-2020-0852) could be exploited to execute malicious code on a Windows system just by getting the user to load an email containing a booby-trapped document in the Microsoft Outlook preview pane. CVE-2020-0852 is one just four remote execution flaws Microsoft patched this month in versions of Word.

One somewhat ironic weakness fixed today (CVE-2020-0872) resides in a new component Microsoft debuted this year called Application Inspector, a source code analyzer designed to help Windows developers identify “interesting” or risky features in open source software (such as the use of cryptography, connections made to a remote entity, etc).

Microsoft said this flaw can be exploited if a user runs Application Inspector on a hacked or booby-trapped program. Whoops. Animesh Jain from security vendor Qualys says this patch should be prioritized, despite being labeled as less severe (“important” versus “critical”) by Microsoft.

For enterprises, Qualys recommends prioritizing the patching of desktop endpoints over servers this month, noting that most of the other critical bugs patched today are prevalent on workstation-type devices. Those include a number of flaws that can be exploited simply by convincing a Windows user to browse to a malicious or hacked Web site.

While many of the vulnerabilities fixed in today’s patch batch affect Windows 7 operating systems, this OS is no longer being supported with security updates (unless you’re an enterprise taking advantage of Microsoft’s paid extended security updates program, which is available to Windows 7 Professional and Windows 7 enterprise users).

If you rely on Windows 7 for day-to-day use, it’s probably time to think about upgrading to something newer. That might be a computer with Windows 10. Or maybe you have always wanted that shiny MacOS computer.

If cost is a primary motivator and the user you have in mind doesn’t do much with the system other than browsing the Web, perhaps a Chromebook or an older machine with a recent version of Linux is the answer (Ubuntu may be easiest for non-Linux natives). Whichever system you choose, it’s important to pick one that fits the owner’s needs and provides security updates on an ongoing basis.

Keep in mind that while staying up-to-date on Windows patches is a must, it’s important to make sure you’re updating only after you’ve backed up your important data and files. A reliable backup means you’re not losing your mind when the odd buggy patch causes problems booting the system.

So do yourself a favor and backup your files before installing any patches. Windows 10 even has some built-in tools to help you do that, either on a per-file/folder basis or by making a complete and bootable copy of your hard drive all at once.

As always, if you experience glitches or problems installing any of these patches this month, please consider leaving a comment about it below; there’s a better-than-even chance other readers have experienced the same and may chime in here with some helpful tips. Also, keep an eye on the AskWoody blog from Woody Leonhard, who keeps a close eye on buggy Microsoft updates each month.

Update, 7:50 p.m.: Microsoft has released an advisory about a remote code execution vulnerability in the way that the Microsoft Server Message Block 3.1.1 (SMBv3) protocol handles certain requests. Critical SMB (Windows file-sharing) flaws are dangerous because they are typically “wormable,” in that they can spread rapidly to vulnerable systems across an internal network with little to no human interaction.

“To exploit the vulnerability against an SMB Server, an unauthenticated attacker could send a specially crafted packet to a targeted SMBv3 Server,” Microsoft warned. “To exploit the vulnerability against an SMB Client, an unauthenticated attacker would need to configure a malicious SMBv3 Server and convince a user to connect to it.”

Microsoft’s advisory says the flaw is neither publicly disclosed nor exploited at the moment. It includes a workaround to mitigate the flaw in file-sharing servers, but says the workaround does not prevent the exploitation of clients.

Microsoft Patch Tuesday, February 2020 Edition

Microsoft today released updates to plug nearly 100 security holes in various versions of its Windows operating system and related software, including a zero-day vulnerability in Internet Explorer (IE) that is actively being exploited. Also, Adobe has issued a bevy of security updates for its various products, including Flash Player and Adobe Reader/Acrobat.

A dozen of the vulnerabilities Microsoft patched today are rated “critical,” meaning malware or miscreants could exploit them remotely to gain complete control over an affected system with little to no help from the user.

Last month, Microsoft released an advisory warning that attackers were exploiting a previously unknown flaw in IE. That vulnerability, assigned as CVE-2020-0674, has been patched with this month’s release. It could be used to install malware just by getting a user to browse to a malicious or hacked Web site.

Microsoft once again fixed a critical flaw in the way Windows handles shortcut (.lnk) files (CVE-2020-0729) that affects Windows 8 and 10 systems, as well as Windows Server 2008-2012. Allan Liska, intelligence analyst at Recorded Future, says Microsoft considers exploitation of the vulnerability unlikely, but that a similar vulnerability discovered last year, CVE-2019-1280, was being actively exploited by the Astaroth trojan as recently as September.

Another flaw fixed this month in Microsoft Exchange 2010 through 2019 may merit special attention. The bug could allow attackers to exploit the Exchange Server and execute arbitrary code just by sending a specially crafted email. This vulnerability (CVE-2020-0688) is rated “important” rather than “critical,” but Liska says it seems potentially dangerous, as Microsoft identifies this as a vulnerability that is likely to be exploited.

In addition, Redmond addressed a critical issue (CVE-2020-0618) in the way Microsoft SQL Server versions 2012-2016 handle page requests.

After a several-month respite from patches for its Flash Player browser plug-in, Adobe has once again blessed us with a security update for this program (fixes one critical flaw). Thankfully, Chrome and Firefox both now disable Flash by default, and Chrome and IE/Edge auto-update the program when new security updates are available. Adobe is slated to retire Flash Player later this year.

Other Adobe products for which the company shipped updates today include Experience Manager, Digital Editions, Framemaker and Acrobat/Reader (17 flaws). Security experts at Qualys note that on January 28th, Adobe also issued an out-of-band patch for Magento, labeled as Priority 2.

“While none of the vulnerabilities disclosed in Adobe’s release are known to be Actively Attacked today, all patches should be prioritized on systems with these products installed,” said Qualys’s Jimmy Graham.

Windows 7 users should be aware by now that while a fair number of flaws addressed this month by Microsoft affect Windows 7 systems, this operating system is no longer being supported with security updates (unless you’re an enterprise taking advantage of Microsoft’s paid extended security updates program, which is available to Windows 7 Professional and Windows 7 enterprise users).

If you rely on Windows 7 for day-to-day use, it’s probably time to think about upgrading to something newer. That might be a computer with Windows 10. Or maybe you have always wanted that shiny MacOS computer.

If cost is a primary motivator and the user you have in mind doesn’t do much with the system other than browsing the Web, perhaps a Chromebook or an older machine with a recent version of Linux is the answer (Ubuntu may be easiest for non-Linux natives). Whichever system you choose, it’s important to pick one that fits the owner’s needs and provides security updates on an ongoing basis.

Keep in mind that while staying up-to-date on Windows patches is a must, it’s important to make sure you’re updating only after you’ve backed up your important data and files. A reliable backup means you’re not losing your mind when the odd buggy patch causes problems booting the system.

So do yourself a favor and backup your files before installing any patches. Windows 10 even has some built-in tools to help you do that, either on a per-file/folder basis or by making a complete and bootable copy of your hard drive all at once.

As always, if you experience glitches or problems installing any of these patches this month, please consider leaving a comment about it below; there’s a better-than-even chance other readers have experienced the same and may chime in here with some helpful tips. Also, keep an eye on the AskWoody blog from Woody Leonhard, who keeps a close eye on buggy Microsoft updates each month.

Patch Tuesday, January 2020 Edition

Microsoft today released updates to plug 50 security holes in various flavors of Windows and related software. The patch batch includes a fix for a flaw in Windows 10 and server equivalents of this operating system that prompted an unprecedented public warning from the U.S. National Security Agency. This month also marks the end of mainstream support for Windows 7, a still broadly-used operating system that will no longer be supplied with security updates.

As first reported Monday by KrebsOnSecurity, Microsoft addressed a severe bug (CVE-2020-0601) in Windows 10 and Windows Server 2016/19 reported by the NSA that allows an attacker to spoof the digital signature tied to a specific piece of software. Such a weakness could be abused by attackers to make malware appear to be a benign program that was produced and signed by a legitimate software company.

An advisory (PDF) released today by the NSA says the flaw may have far more wide-ranging security implications, noting that the “exploitation of the vulnerability allows attackers to defeat trusted network connections and deliver executable code while appearing as legitimately trusted entities.”

“NSA assesses the vulnerability to be severe and that sophisticated cyber actors will understand the underlying flaw very quickly and, if exploited, would render the previously mentioned platforms as fundamentally vulnerable,” the advisory continues. “The consequences of not patching the vulnerability are severe and widespread.”

Matthew Green, an associate professor in the computer science department at Johns Hopkins University, said the flaw involves an apparent implementation weakness in a component of recent Windows versions responsible for validating the legitimacy of authentication requests for a panoply of security functions in the operating system.

Green said attackers can use this weakness to impersonate everything from trusted Web sites to the source of software updates for Windows and other programs.

“Imagine if I wanted to pick the lock in your front door,” Green analogized. “It might be hard for me to come up with a key that will open your door, but what if I could tamper with or present both the key and the lock at the same time?”

Kenneth White, security principal at the software company MongoDB, equated the vulnerability to a phone call that gets routed to a party you didn’t intend to reach.

“You pick up the phone, dial a number and assume you’re talking to your bank or Microsoft or whomever, but the part of the software that confirms who you’re talking to is flawed,” White said. “That’s pretty bad, especially when your system is saying download this piece of software or patch automatically and it’s being done in the background.”

Both Green and White said it likely will be a matter of hours or days before security researchers and/or bad guys work out ways to exploit this bug, given the stakes involved. Indeed, already this evening KrebsOnSecurity has seen indications that people are teasing out such methods, which will likely be posted publicly online soon.

According to security vendor Qualys, only eight of the 50 flaws fixed in today’s patch roundup from Microsoft earned the company’s most dire “critical” rating, a designation reserved for bugs that can be exploited remotely by malware or miscreants to seize complete control over the target computer without any help from users.

Once again, some of those critical flaws include security weaknesses in the way Windows implements Remote Desktop connections, a feature that allows systems to be accessed, viewed and controlled as if the user was seated directly in front of the remote computer. Other critical patches include updates for the Web browsers and Web scripting engines built into Windows, as well as fixes for ASP.NET and the .NET Framework.

The security fix for the CVE-2020-0601 bug and others detailed in this post will be offered to Windows users as part of a bundle of patches released today by Microsoft. To see whether any updates are available for your Windows computer, go to the Start menu and type “Windows Update,” then let the system scan for any available patches.

Keep in mind that while staying up-to-date on Windows patches is a must, it’s important to make sure you’re updating only after you’ve backed up your important data and files. A reliable backup means you’re not losing your mind when the odd buggy patch causes problems booting the system. So do yourself a favor and backup your files before installing any patches. Windows 10 even has some built-in tools to help you do that, either on a per-file/folder basis or by making a complete and bootable copy of your hard drive all at once.

Today also marks the last month in which Microsoft will ship security updates for Windows 7 home/personal users. I count myself among some 30 percent of Windows users who still like and (ab)use this operating system in one form or another, and am sad that this day has come to pass. But if you rely on this OS for day-to-day use, it’s probably time to think about upgrading to something newer.

That might be a computer with Windows 10. Or maybe you have always wanted that shiny MacOS computer. If cost is a primary motivator and the user you have in mind doesn’t do much with the system other than browsing the Web, perhaps a Chromebook or an older machine with a recent version of Linux is the answer. Whichever system you choose, it’s important to pick one that fits the owner’s needs and provides security updates on an ongoing basis.

As always, if you experience glitches or problems installing any of these patches this month, please consider leaving a comment about it below; there’s a better-than-even chance other readers have experienced the same and may chime in here with some helpful tips.