Category Archives: Ghacks.net

Patch Tuesday Lowdown, April 2019 Edition

Microsoft today released fifteen software updates to fix more than 70 unique security vulnerabilities in various flavors of its Windows operating systems and supported software, including at least two zero-day bugs. These patches apply to Windows, Internet Explorer (IE) and Edge browsers, Office, Sharepoint and Exchange. Separately, Adobe has issued security updates for Acrobat/Reader and Flash Player.

According to security firm Rapid 7, two of the vulnerabilities — CVE-2019-0803 and CVE-2019-0859 — are already being exploited in the wild. They can result in unauthorized elevation of privilege, and affect all supported versions of Windows.

“An attacker must already have local access to an affected system to use these to gain kernel-level code execution capabilities,” Rapid7 researcher Greg Wiseman observed. “However, one of the 32 Remote Code Execution (RCE) vulnerabilities patched today could potentially be used with them in an exploit chain to obtain full control of a system.”

Aside from these zero-day privilege escalation flaws, Wiseman said, it’s a fairly standard Patch Tuesday.

“Which of course still means that there are bugs that should be patched as soon as possible, such as the eight vulnerabilities classified as critical in the scripting engine used by Microsoft browsers, and CVE-2019-0822 (an RCE in Microsoft Office that can be exploited by convincing a user to open a malicious file).”

Adobe’s Patch Tuesday includes security updates for its Flash Player and AIR software,  as well as Adobe Reader and Acrobat.

Flash updates are installed along with other monthly Windows patch rollups for consumers, and auto-installed by Google Chrome, but users may need to reboot the operating system (in the case of IE/Edge) or the browser (in Chrome) for the new updates to take effect.

Adobe’s actions also sound the death knell for Adobe Shockwave Player, which has at long last reached end-of-life.

That means no more security updates for Shockwave, which has always been something of an ugly stepchild to Flash. That is to say, Shockwave never really got the security attention Flash has received but nevertheless has been just as vulnerable and often lagging months or years behind Flash in terms of updates.

Chris Goettl, director of product management and security for security firm Ivanti, said Windows users need to get any existing Shockwave installations out of their environments now.

“There are 7 vulnerabilities that are going to be vulnerable for the majority of Shockwave installs still in existence,” Goettl said. “You can bet an exploit is imminent there.”

Standard advice: Staying up-to-date on Windows patches is good. Updating only after you’ve backed up your important data and files is even better. A good backup means you’re not pulling your hair out if the odd buggy patch causes problems booting the system.

Windows 10 likes to install patches all in one go and reboot your computer on its own schedule. Microsoft doesn’t make it easy for Windows 10 users to change this setting, but it is possible. For all other Windows OS users, if you’d rather be alerted to new updates when they’re available so you can choose when to install them, there’s a setting for that in Windows Update.

As always, if you experience any problems installing any of these patches this month, please feel free to leave a comment about it below; there’s a good chance other readers have experienced the same and may even chime in here with some helpful tips.

Further reading:

Qualys on Patch Tuesday

SANS Internet Storm Center’s Patch Tuesday Priorities.

Martin Brinkmann of Ghacks.net

Patch Tuesday, January 2019 Edition

Microsoft on Tuesday released updates to fix roughly four dozen security issues with its Windows operating systems and related software. All things considered, this first Patch Tuesday of 2019 is fairly mild, bereft as it is of any new Adobe Flash updates or zero-day exploits. But there are a few spicy bits to keep in mind. Read on for the gory details.

The updates released Tuesday affect Windows, Internet Explorer and Edge, Office, Sharepoint, .NET Framework and Exchange. Patches are available for all client and server versions of Windows, but none of the “critical” flaws — those that can lead to a remote system compromise without any help from users — apply to Windows 7 or Windows 8.1, according to Martin Brinkmann at Ghacks.net.

Mercifully, none of the vulnerabilities fixed in Tuesday’s bundle are being actively exploited, although one (CVE-2019-0579) was publicly disclosed prior to the patch release, meaning attackers may have had a head start figuring out how to exploit it. This bug is one of 11 that Microsoft fixed in its Jet Database Engine.

Among the more eyebrow-raising flaws fixed this week is CVE-2019-0547, a weakness in the Windows component responsible for assigning Internet addresses to host computers (a.k.a. “Windows DHCP client”). According to security vendor Tenable, this is the most severe bug of the entire patch batch.

“In order to exploit the vulnerability, an attacker would need to be able to send a specially crafted DHCP response to its target, allowing them to run arbitrary code on the client machine,” said Satnam Narang, senior research engineer at Tenable.

Tuesday’s update bundle also includes a fix that Microsoft released late last month as an emergency patch to plug a zero-day flaw in Internet Explorer (CVE-2018-8653) that attackers are already exploiting. Experts at Recorded Future say that vulnerability continues to be exploited in the wild, with several exploit kits now including the publicly released proof-of-concept code into their platforms.

“If you have not patched this vulnerability yet, it should be the number one priority,” writes Allan Liska, senior solutions architect at Recorded Future.

It generally can’t hurt for Windows users to wait a day or two after Microsoft releases monthly security updates before installing the fixes; occasionally buggy patches can cause serious headaches for users who install them before all the kinks are worked out.

Case in point: Computerworld’s Woody Leonhard notes that multiple organizations are reporting problems with their file-sharing operations after installing this month’s patch rollup.

Windows 10 likes to install patches all in one go and reboot your computer on its own schedule. Microsoft doesn’t make it easy for Windows 10 users to change this setting, but it is possible. For all other Windows OS users, if you’d rather be alerted to new updates when they’re available so you can choose when to install them, there’s a setting for that in Windows Update. Also, it’s a good idea to get in the habit of backing up your data before installing Windows updates.

Adobe released an update for its Flash Player plugin, but alas there don’t appear to be any security fixes in it. However, the company last Thursday did release new versions of its Adobe Acrobat and Reader that correct at least two critical vulnerabilities in each.

If you experience any problems installing any of these patches this month, please feel free to leave a comment about it below; there’s a good chance other readers have experienced the same and may even chime in here with some helpful tips.