Monthly Archives: May 2019

May 2019 Update Summary

Note to my readers:

Due to professional commitments over the last several weeks and for the next 2 weeks; updates and new content to this blog have been and will be delayed. I’ll endeavour to return to a routine manner of posting as soon as possible.

Thank you.

Earlier today Microsoft and Adobe released their monthly security updates. Microsoft resolved 79 vulnerabilities (more formally known as CVEs (defined) with Adobe addressing 87 vulnerabilities.

Adobe Acrobat and Reader: 84x priority 2 vulnerabilities (48x Critical and 36x Important severity)

Adobe Flash: 1x priority 2 vulnerability (1x Critical severity)

Adobe Media Encoder: 2x priority 3 vulnerabilities (1x Critical severity and 1x Important severity)

If you use Acrobat/Reader or Flash, please apply the necessary updates as soon as possible. Please install their remaining priority 3 update when time allows.

For Microsoft; this month’s list of Known Issues is available within their monthly summary page and applies to all currently supported operating systems. All issues however do have at least 1 workaround:

4493730   Windows Server 2008 Service Pack 2 (Servicing Stack Update)

4494440   Windows 10, version 1607, Windows Server 2016

4494441   Windows 10, version 1809, Windows Server 2019

4497936   Windows 10, version 1903

4498206   Internet Explorer Cumulative Update

4499151   Windows 8.1, Windows Server 2012 R2 (Monthly Rollup)

4499154   Windows 10

4499158   Windows Server 2012 (Security-only update)

4499164   Windows 7 Service Pack 1, Windows Server 2008 R2 Service Pack 1

4499165   Windows 8.1 Windows Server 2012 R2 (Security-only update)

4499167   Windows 10, version 1803

4499171   Windows Server 2012 (Monthly Rollup)

4499179   Windows 10, version 1709

4499180   Windows Server 2008 Service Pack 2 (Security-only update)

4499181  Windows 10, version 1703

US Computer Emergency Readiness Team (CERT) (please see the “Information on Security Updates” heading of the “Protecting Your PC” page):

A further useful source of update related information is the Calendar of Updates.

News/announcements of updates in the categories of General SoftwareSecurity Software and Utilities are available on their website. The news/announcements are very timely and (almost always) contain useful direct download links as well as the changes/improvements made by those updates (where possible).

If you like and use it, please also consider supporting that entirely volunteer run website by donating.

For this month’s Microsoft updates, I will prioritize the order of installation below:
Windows RDP: CVE-2019-0708 (also includes an update for Windows Server 2003 and Windows XP)

Scripting Engine: CVE-2019-0924 ,  CVE-2019-0927 , CVE-2019-0922 , CVE-2019-0884 , CVE-2019-0925 , CVE-2019-0937 , CVE-2019-0918 , CVE-2019-0913 , CVE-2019-0912 , CVE-2019-0911 , CVE-2019-0914 , CVE-2019-0915 , CVE-2019-0916 , CVE-2019-0917

Windows DHCP Server: CVE-2019-0725

Microsoft Word: CVE-2019-0953

Microsoft Graphics Component: CVE-2019-0903

Microsoft Edge and Internet Explorer (multiple versions of Edge and IE affected)

Windows Error Reporting: CVE-2019-0863

Microsoft Advisory for Adobe Flash Player

Microsoft Windows Servicing Stack Updates

For the Intel Microarchitectural Data Sampling (MDS) vulnerabilities, please follow the advice of Intel and Microsoft within their advisories. A more thorough list of affected vendors is available from here.

Please install the remaining updates at your earliest convenience.

As per standard best practice; I would recommend backing up the data on any device for which you are installing updates to prevent data loss in the rare event that any update causes unexpected issues. I have provided further details of updates available for other commonly used applications below.

Thank you.

Nvidia Graphics Drivers:
3 security vulnerabilities with the most severe having a CVSS V3 (defined) base score of 7.7 have been resolved within Nvidia’s graphics card drivers (defined) in May. These vulnerabilities affect Windows only. All 3 are local vulnerabilities rather than remote meaning that an attacker would first need to compromise your system before exploiting the Nvidia vulnerabilities to elevate their privileges. The steps to install the drivers are located here. If you use affected Nvidia graphics card, please consider updating your drivers to the most recent available.

VMWare has released the following security advisories:

Workstation Pro:

Security Advisory 1: Addresses 1x DLL hijacking vulnerability (defined)

Security Advisory 2: Addresses 4x vulnerabilities present in Workstation Pro and the products listed below. Please make certain to install Intel microcode updates as they become available for your systems as they become available in addition to these VMware updates:

VMware vCenter Server (VC)
VMware vSphere ESXi (ESXi)
VMware Fusion Pro / Fusion (Fusion)
vCloud Usage Meter (UM)
Identity Manager (vIDM)
vCenter Server (vCSA)
vSphere Data Protection (VDP)
vSphere Integrated Containers (VIC)
vRealize Automation (vRA)

If you use the above VMware products, please review the security advisories and apply the necessary updates.

Thank you.

No Fix Planned for Linksys Router Information Disclosure

Earlier this week a security researcher disclosed a vulnerability within Linksys routers that was thought to have been patched back in 2014.

TL DR: No fix for this vulnerability exists. It is made worse if your router is using the default password. With no fix from Linksys expected you may consider using OpenWrt firmware.

Why should this vulnerability be considered important?
This vulnerability is trivial to exploit and can be carried out remotely by an un-skilled attacker. A list of affected Linksys routers is available in Mursch’s report At the time of writing, Linksys have deemed the vulnerability “Not applicable / Won’t fix” following responsible disclosure by Mursch. This information disclosure vulnerability leaks (among other details):

  • MAC address (defined) of every device that’s ever connected to it (full historical record, not just active devices)
  • Device name (such as “TROY-PC” or “Mat’s MacBook Pro”)
  • Operating system (such as “Windows 7” or “Android”)
  • WAN settings
  • Firewall status
  • Firmware update settings
  • DDNS settings

A further example of the information disclosed is present in Mursch’s report. One of the more important elements disclosed is the MAC address. This unique “fingerprint” allows the tracking of a device as it moves across networks and allowing it’s geolocation using a service such as Wigle (we have mentioned Wigle before on this blog). Using this location data, an attacker could plan and conduct targeted attacks against your business/home.

As mentioned above; this vulnerability is made more severe if your Linksys router is using a default password; the following actions can be taken by an attacker (list courtesy of Mr. Troy Mursch):

  • Obtain the SSID and Wi-Fi password in plaintext
  • Change the DNS settings to use a rogue DNS server to hijack web traffic
  • Open ports in the router’s firewall to directly target devices behind the routers (example: 3389/TCP for Windows RDP)
  • Use UPnP to redirect outgoing traffic to the threat actors’ device
  • Create an OpenVPN account (supported models) to route malicious traffic through the router
  • Disable the router’s internet connection or modify other settings in a destructive manner

How can I protect my organisation/myself from this vulnerability?
If your router is one of the vulnerable models listed in Mursch’s report; please make certain the option for automatic firmware updates is enabled (if it is present). Should Linksys correct this vulnerability in the future, you will receive the fix automatically.

Please make certain your Linksys router is not using the default password it is supplied with. With no fix from Linksys expected you may consider using OpenWrt firmware.

Thank you.