Microsoft fixes critical vulnerabilities in IE, Edge, Office, and Windows print services

July's Patch Tuesday brings fixes for 47 vulnerabilities across Microsoft's products

Microsoft's new batch of security patches fixes 47 vulnerabilities across its products, including in Internet Explorer, Edge, Office, Windows and the .NET Framework.

The patches, released Tuesday, are arranged in 11 security bulletins, 10 of which are for Microsoft products. The remaining patch covers Adobe Flash Player, which is bundled with Internet Explorer in Windows 8.1, Windows Server 2012, Windows RT 8.1, Windows Server 2012 R2 and Windows 10.

Six security bulletins, including the Flash Player one, are rated critical and primarily cover remote code execution vulnerabilities that could lead to a complete system compromise.

Aside from the typical browser flaws that can be exploited through malicious web pages and those in Office that can be exploited through specifically crafted documents, two others stand out: one in the JScript and VBScript scripting engines of Windows and one in the operating system's Print Spooler service.

The scripting engine flaw could allow remote code execution with the privileges of the current user. It can be exploited through malicious code hosted on websites or through an ActiveX control marked as "safe for initialization" in an application or Microsoft Office document that hosts the IE rendering engine.

The Print Spooler service flaw is even more serious. It allows an attacker who compromises a network printer or who can spoof a printer on the network to trick a user's computer into installing a malicious printer driver when connecting to a new printer. Because this would be a system driver, the attacker's malicious code would be executed with system-level privileges.

Even worse, the flaw can also be exploited from outside the network if the user visits a compromised web page or loads a malicious ad in his browser, according to researchers from Vectra who discovered the issue. That's possible because the Internet Printing Protocol (IPP) and the web Point-and-Print Protocol allow the same seamless installation of printer drivers that happens over the local network when adding a new printer.

As usual, companies should prioritize the patches described in the critical-rated bulletins, but should also review the ones rated as important, as they could prove urgent for their specific environments.

One of this month's bulletins rated as important covers a privilege escalation vulnerability in kernel-mode drivers. This type of vulnerability is important in modern exploit chains and is used in targeted attacks to gain full control over systems after limited accounts have been compromised through other flaws.

Another bulletin covers a vulnerability that could allow attackers to bypass the Windows Secure Boot feature if an attacker gains administrative privileges and installs an affected policy on a system. Secure Boot uses cryptographic verifications to ensure that only digitally signed and approved code is loaded during the system boot-up, therefore preventing the installation of stealthy, boot-level rootkits.

"An attacker who successfully exploited this vulnerability could disable code integrity checks, allowing test-signed executables and drivers to be loaded on a target device," Microsoft said in the security bulletin. "In addition, an attacker could bypass the Secure Boot Integrity Validation for BitLocker and the Device Encryption security features."

Join the CSO newsletter!

Error: Please check your email address.

More about Microsoft

Show Comments

Featured Whitepapers

Editor's Recommendations

Solution Centres

Stories by Lucian Constantin

Latest Videos

  • 150x50

    CSO Webinar: The Human Factor - Your people are your biggest security weakness

    ​Speakers: David Lacey, Researcher and former CISO Royal Mail David Turner - Global Risk Management Expert Mark Guntrip - Group Manager, Email Protection, Proofpoint

    Play Video

  • 150x50

    CSO Webinar: Current ransomware defences are failing – but machine learning can drive a more proactive solution

    Speakers • Ty Miller, Director, Threat Intelligence • Mark Gregory, Leader, Network Engineering Research Group, RMIT • Jeff Lanza, Retired FBI Agent (USA) • Andy Solterbeck, VP Asia Pacific, Cylance • David Braue, CSO MC/Moderator What to expect: ​Hear from industry experts on the local and global ransomware threat landscape. Explore a new approach to dealing with ransomware using machine-learning techniques and by thinking about the problem in a fundamentally different way. Apply techniques for gathering insight into ransomware behaviour and find out what elements must go into a truly effective ransomware defence. Get a first-hand look at how ransomware actually works in practice, and how machine-learning techniques can pick up on its activities long before your employees do.

    Play Video

  • 150x50

    CSO Webinar: Get real about metadata to avoid a false sense of security

    Speakers: • Anthony Caruana – CSO MC and moderator • Ian Farquhar, Worldwide Virtual Security Team Lead, Gigamon • John Lindsay, Former CTO, iiNet • Skeeve Stevens, Futurist, Future Sumo • David Vaile - Vice chair of APF, Co-Convenor of the Cyberspace Law And Policy Community, UNSW Law Faculty This webinar covers: - A 101 on metadata - what it is and how to use it - Insight into a typical attack, what happens and what we would find when looking into the metadata - How to collect metadata, use this to detect attacks and get greater insight into how you can use this to protect your organisation - Learn how much raw data and metadata to retain and how long for - Get a reality check on how you're using your metadata and if this is enough to secure your organisation

    Play Video

  • 150x50

    CSO Webinar: How banking trojans work and how you can stop them

    CSO Webinar: How banking trojans work and how you can stop them Featuring: • John Baird, Director of Global Technology Production, Deutsche Bank • Samantha Macleod, GM Cyber Security, ME Bank • Sherrod DeGrippo, Director of Emerging Threats, Proofpoint (USA)

    Play Video

  • 150x50

    IDG Live Webinar:The right collaboration strategy will help your business take flight

    Speakers - Mike Harris, Engineering Services Manager, Jetstar - Christopher Johnson, IT Director APAC, 20th Century Fox - Brent Maxwell, Director of Information Systems, THE ICONIC - IDG MC/Moderator Anthony Caruana

    Play Video

More videos

Blog Posts