Tag Archives: VMware

Linux TCP SACK Vulnerabilities June 2019

Earlier this week; Netflix’s Cybersecurity team disclosed 3 denial of service vulnerabilities within the Linux kernels (defined) affecting Amazon AWS, Debian, Red Hat, FreeBSD (only 1 vulnerability affects FreeBSD), SUSE and Ubuntu distributions.

================
TL DR:
If you use Amazon AWS, Debian FreeBSD, Red Hat, SUSE or Ubuntu, please install the relevant vendor updates or implement the workarounds both linked to below.
================

Why should these vulnerabilities be considered important?
All of these vulnerabilities are remotely exploitable. The most serious of which has been given the name “SACK Panic” (CVE-2019-11477) is most likely to be present/enabled in web servers used to run both large and small business or personal websites. Exploiting this issue will lead to your server crashing/becoming unresponsive. It has a CVSS 3 base score of 7.5 (high severity) and with a low complexity for an attacker to leverage.

The second vulnerability CVE-2019-11478 which can cause “SACK Slowness” is also remotely exploitable but is of moderate severity. If an attacker were to create and send a series of SACK packets it can cause the affected Linux systems to use too much resources (both memory and CPU). FreeBSD is vulnerable to a variation of this CVE-2019-5599.

The third and final vulnerability CVE-2019-11479 is again moderate severity causing high resource usage. In this instance; when an attacker would need to set the maximum segment size (MSS) of a TCP connection to it’s smallest limit of 48 bytes and then send a sequence of specially crafted SACK packets.

The name SACK is derived from TCP Selective Acknowledgement (SACK) packets used to speed up TCP re-transmits by informing a sender (in a two-way data transfer) of which data packets have been already been received successfully.

================

How can I protect my organisation or myself from these vulnerabilities?
The affected vendors have released updates or workarounds for these vulnerabilities; links to their advisories and recommended actions are provided below.

At this time, it is not known if Apple macOS (which originated from FreeBSD) is affected. It is not mentioned in any of the advisories. Should an advisory be released it will be available from Apple’s dedicated security page.

================

Amazon AWS:
https://aws.amazon.com/security/security-bulletins/AWS-2019-005/

Debian:
https://security-tracker.debian.org/tracker/CVE-2019-11477

https://security-tracker.debian.org/tracker/CVE-2019-11478

https://security-tracker.debian.org/tracker/CVE-2019-11479

FreeBSD:
https://github.com/Netflix/security-bulletins/blob/master/advisories/third-party/2019-001/split_limit.patch

RedHat:
https://access.redhat.com/security/vulnerabilities/tcpsack

SUSE:
https://www.suse.com/support/kb/doc/?id=7023928

Ubuntu:
https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/SACKPanic

====================
Updated: 9th July 2019
====================
On the 2nd of July 2019; VMware issued some updates for this set of vulnerabilities that affects it’s products. Further updates are pending. If you use any of the following VMware products, please review this security advisory and apply the updates as they become available:

AppDefense
Container Service Extension
Enterprise PKS
Horizon
Horizon DaaS
Hybrid Cloud Extension
Identity Manager
Integrated OpenStack
NSX for vSphere
NSX-T Data Center
Pulse Console
SD-WAN Edge by VeloCloud
SD-WAN Gateway by VeloCloud
SD-WAN Orchestrator by VeloCloud
Skyline Collector
Unified Access Gateway
vCenter Server Appliance
vCloud Availability Appliance
vCloud Director For Service Providers
vCloud Usage Meter
vRealize Automation
vRealize Business for Cloud
vRealize Code Stream
vRealize Log Insight
vRealize Network Insight
vRealize Operations Manager
vRealize Orchestrator Appliance
vRealize Suite Lifecycle Manager
vSphere Data Protection
vSphere Integrated Containers
vSphere Replication

Thank you.

June 2019 Update Summary

With yesterday being the second Tuesday of the month; it means it’s Update Tuesday again. Microsoft resolved 88 vulnerabilities  (more formally known as CVEs (defined) with Adobe addressing 11 vulnerabilities of their own.

Adobe Campaign: 7x Priority 3 vulnerabilities (1x Critical, 3x Important, 3x Moderate)

Adobe ColdFusion: 3x Priority 2 vulnerabilities (3x Critical)

Adobe Flash Player: 1x Priority 1 vulnerability (1x Critical)

If you use Adobe ColdFusion, please apply the necessary updates as soon as possible. For that product, as per Adobe’s advisory, please make certain the Java JDK/JRE in use on the server is fully up to date in order to fully secure it. Please install the remaining updates for Campaign and Flash Player as soon as possible since they also resolve critical vulnerabilities.

====================
For Microsoft; this month’s list of Known Issues is available within their monthly summary page and applies to all currently supported operating systems. Not all issues have workarounds at this time. Windows 7 SP1, Windows Server 2008 R2 SP1 and Windows 8.1 and Windows Server 2012 R2 list known issues with McAfee products and should refer to the guidance linked to by Microsoft within the above linked to attempt to workaround these issues:

4493730                Windows Server 2008 Service Pack 2 Servicing stack update

4503027                Exchange Server 2019, Exchange Server 2016

4503028                Exchange Server 2010 Service Pack 3, Exchange Server 2013

4503263                Windows Server 2012 (Security-only update)

4503267                Windows 10, version 1607, Windows Server 2016

4503276                Windows 8.1, Windows Server 2012 R2 (Monthly Rollup)

4503279                Windows 10, version 1703

4503284                Windows 10, version 1709

4503285                Windows Server 2012 (Monthly Rollup)

4503286                Windows 10, version 1803

4503290                Windows 8.1 Windows Server 2012 R2 (Security-only update)

4503291                Windows 10

4503292                Windows 7 Service Pack 1, Windows Server 2008 R2 Service Pack 1 (Security-only update)

4503293                Windows 10, version 1903

4503327                Windows 10, version 1809, Windows Server 2019

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

https://www.us-cert.gov/

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:
====================
Microsoft Edge and Internet Explorer: CVE-2019-1038

Microsoft Speech API Remote Code Execution Vulnerability: CVE-2019-0985

Microsoft Scripting Engine:

CVE-2019-1002

CVE-2019-0991

CVE-2019-1080

CVE-2019-1023

CVE-2019-0992

CVE-2019-1024

CVE-2019-0990

CVE-2019-0988

CVE-2019-0989

CVE-2019-1055

CVE-2019-1052

CVE-2019-1051

CVE-2019-0920

CVE-2019-1003

Windows Hyper-V Remote Code Execution Vulnerability: CVE-2019-0709 , CVE-2019-0722 , CVE-2019-0620

ActiveX Data Objects (ADO) Remote Code Execution Vulnerability: CVE-2019-0888

Windows Task Scheduler: CVE-2019-1069 (disclosed by SandboxEscaper)

Windows AppX Deployment Service (AppXSVC): CVE-2019-1064 (disclosed by SandboxEscaper)

Windows Shell: CVE-2019-1053 (disclosed by SandboxEscaper)

Windows Installer: CVE-2019-0973 (disclosed by SandboxEscaper)

====================
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.

=======================
VideoLAN VLC:
=======================
A new version of VLC is available for Apple macOS, Linux, Windows (desktop and Windows Store), Google Android and Apple iOS with some great performance improvements and resolving 33 security vulnerabilities (2 of which are high severity) as a result of the EU-FOSSA bug bounty programme which opened in January this year.

Further details are below:

http://www.videolan.org/vlc/releases/3.0.7.html

http://www.jbkempf.com/blog/post/2019/VLC-3.0.7-and-security

Version 3.0.7.1 has since been released to resolve other non-security issues. The most recent version can be downloaded from:

http://www.videolan.org/vlc/

=======================
Mozilla Firefox
=======================
Yesterday (11th June), Mozilla released Firefox 67.0.2 to address a single moderate severity vulnerability.

Further to the above updates, on the 18th and the 20th June; Mozilla issued 2 updates for Firefox version 67.0.3 (ESR (Extended Support Release) 60.7.1) and 67.0.4 (ESR 60.7.2) to resolve 2x critical zero day (defined) vulnerabilities actively being exploited in the wild.

Details of how to install updates for Firefox are here. If Firefox is your web browser of choice, if you have not already done so, please update it as soon as possible to benefit from the above changes.

=======================
Google Chrome:
=======================
Google released Google Chrome version 75.0.3770.80 to address 42 vulnerabilities in early June.

Google Chrome updates automatically and will apply the update the next time Chrome is closed and then re-opened. Chrome can also be updated immediately by clicking the Options button (it looks like 3 stacked small horizontal lines, sometimes called a “hamburger” button) in the upper right corner of the window and choosing “About Google Chrome” from the menu. Follow the prompt to Re-launch Chrome for the updates to take effect.

=======================
VMware:
=======================
Earlier this month VMware published a security advisory to address a single Important severity vulnerability in VMware Tools for Linux and Windows.

If you use VMware Tools on Linux or Windows, please review the security advisory and apply the necessary updates.

Thank you.

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):

https://www.us-cert.gov/

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
=======================
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.

Pwn2Own 2019 Results

TL DR: With popular products such as the Tesla Model 3, Apple Safari, Mozilla Firefox, Oracle VirtualBox, VMware Workstation Pro and Microsoft Edge being successfully exploited; please install the necessary updates when they become available.

The annual white hat hacking contest known as Pwn2Own took place last week. Detailed results from all 3 days are available from this link.

Day 3 saw initially two teams attempting to exploit a Tesla Model 3 before one withdrew. The team Fluoroacetate made up of both Richard Zhu and Amat Cama successfully exploited the infotainment system of the Tesla earning them a further $35,000 and the car itself. They earned $375k in total and became the Master of Pwn for 2019. The contest overall distributed $545k for 19 vulnerabilities.

In contrast to previous years the researchers have targeted vulnerabilities other than those within the operating system kernel (defined) to obtain a total system compromise. Only 3 times were exploits on the OS kernel used this year (one exploit was used in conjunction when exploiting each of the web browsers Apple Safari, Microsoft Edge and Mozilla Firefox).

We can expect updates for each of the exploited products over the coming weeks and months (the vendors have up to 120 days to resolve the vulnerabilities before public disclosure). Mozilla released Firefox 66.0.1 and 60.6.1 to resolve the 2 Firefox CVEs (defined) disclosed during the contest.

If you use the affected products, please keep current with the necessary updates. Thank you.

March 2019 Update Summary

====================
Updated: 21st March 2019
====================
Two of the vulnerabilities patched by Microsoft (CVE-2019-0797CVE-2019-0808) were zero day (defined) vulnerabilities being actively exploited in the wild. Four other vulnerabilities were publicly known (CVE-2019-0683CVE-2019-0754CVE-2019-0757 and CVE-2019-0809).

Separately the Google Chrome vulnerability mentioned below namely CVE-2019-5786 was also being exploited by attackers.

After publishing my original post; Adobe and Microsoft jointly reported that while a newer version (32.0.0.156) of Flash Player was made available it only resolves non-security bugs.

I have updated the suggested installation order (below) to reflect this new information. Thank you.

====================
Original Post:
====================
As scheduled; earlier today Microsoft and Adobe made available their security updates. Microsoft addressed 65 vulnerabilities (more formally known as CVEs (defined)) with Adobe resolving 2 vulnerabilities.

For Adobe; if you have not already done so; if you manage an installation of Adobe ColdFusion or know someone who does, please apply the necessary updates made available earlier this month. That update addressed a single priority 1 zero day (defined) vulnerability being exploited in the wild. Today’s Adobe updates are as follows:

Adobe Digital Editions: 1x priority 3 CVE resolved

Adobe Photoshop CC: 1x priority3 CVE resolved

If you use the affected Adobe products; please install their remaining priority 3 updates when you can.

This month’s list of Known Issues is now sorted by Microsoft within their monthly summary page and applies to all currently supported operating systems:

KB4489878          Windows 7 Service Pack 1, Windows Server 2008 R2 Service Pack 1 (Monthly Rollup)

KB4489881          Windows 8.1, Windows Server 2012 R2 (Monthly Rollup)

KB4489882          Windows 10 version 1607, Windows Server 2016

KB4489883          Windows 8.1, Windows Server 2012 R2 (Security-only update)

KB4489884          Windows Server 2012 (Security-only update)

KB4489885          Windows 7 Service Pack 1, Windows Server 2008 R2 Service Pack 1 (Security-only update)

KB4489891          Windows Server 2012 (Monthly Rollup)

KB4489899          Windows 10 version 1809, Windows Server 2019

You can monitor the availability of security updates for most your software from the following websites (among others) or use one of the utilities presented on this page:

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

https://www.us-cert.gov/

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

Windows Kernel: CVE-2019-0797CVE-2019-0808

Windows DHCP Client: CVE-2019-0697 , CVE-2019-0698 , CVE-2019-0726

Microsoft XML: CVE-2019-0756

Scripting Engine: CVE-2019-0592 , CVE-2019-0746 , CVE-2019-0639 , CVE-2019-0783 , CVE-2019-0609 , CVE-2019-0611 , CVE-2019-0666 , CVE-2019-0769 , CVE-2019-0665 , CVE-2019-0667 , CVE-2019-0680 , CVE-2019-0773 , CVE-2019-0770 , CVE-2019-0771 , CVE-2019-0772

Visual Studio Remote Code Execution Vulnerability: CVE-2019-0809

Microsoft Active Directory: CVE-2019-0683

NuGet Package Manager Tampering Vulnerability: CVE-2019-0757

Windows Denial of Service Vulnerability: CVE-2019-0754

Microsoft Dynamics 365: a privilege escalation vulnerability (defined) has been addressed (this product is also widely deployed)

If you use Microsoft IIS (Internet Information Services), please review advisory: ADV190005

====================
Please install the remaining updates at your earliest convenience.

As always; 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.

=======================
Google Chrome:
=======================
Google released Google Chrome version 72.0.3626.121 to address a single zero day (defined) vulnerability under active exploit. The vulnerability was a high severity use-after-free (defined) flaw in Chrome’s FileReader API (defined) which could have led to information disclosure of files stored on the same system as Chrome is installed.

Google Chrome updates automatically and will apply the update the next time Chrome is closed and then re-opened. Chrome can also be updated immediately by clicking the Options button (it looks like 3 stacked small horizontal lines, sometimes called a “hamburger” button) in the upper right corner of the window and choosing “About Google Chrome” from the menu. Follow the prompt to Re-launch Chrome for the updates to take effect.

=======================
Notepad++:
=======================
Notepad++ 7.6.4 was released on the 6th of March resolving 8 security issues. This version follows another from January which resolved 7 other vulnerabilities. If you use Notepad++, please update to the newest version to benefit from these security fixes.

Notepad++ 7.6.6 was released to resolve a critical regression in 7.6.5 which caused Notepad++ to crash. Version 7.6.5 resolved a further 6 security vulnerabilities.

If you use Notepad++, please update to the newest version to benefit from these reliability and security fixes.

Thank you.

=======================
Mozilla Firefox
=======================
Update: 25th March 2019: As detailed in the Pwn2Own 2019 results post; Mozilla released a further update for Firefox and Firefox ESR bringing their version numbers to 66.0.1 and 60.6.1 respectively. Both updates resolve 2x critical CVEs. Please consider updating to these versions as soon as possible.

=======================
In the latter half of March Mozilla issued updates for Firefox 66 and Firefox ESR (Extended Support Release) 60.6:

Firefox 66.0: Resolves 5x critical CVEs (defined), 7x high CVEs, 5x moderate CVEs and 4x low CVEs

Firefox 60.6: Resolves 4x critical critical CVEs, 4x high CVEs and 2x moderate CVEs

Firefox 66 introduces better reliability (since crashes have been reduced) and improved performance. In addition, smooth scrolling has been added. The blocking of websites automatically playing audio or video content is now also present. These and other features are discussed in more depth here and here.

Details of how to install updates for Firefox are here. If Firefox is your web browser of choice, if you have not already done so, please update it as soon as possible to benefit from the above changes.

=======================
VMware:
=======================
VMware issued 2 security advisories during March:
Security Advisory 1: Addresses 2x important severity CVEs in the following products:

VMware Player
VMware Workstation Pro

Security Advisory 2: Addresses 1x moderate severity CVE in the following products:

VMware Horizon

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

=======================
Putty:
=======================
Putty, the open source and highly popular SSH (defined) client for Windows, was updated to version 0.71 in mid-March. It contains 8 security fixes (see below). They are a result of the bug bounties awarded through the EU-Free and Open Source Software Auditing (EU-FOSSA) (discussed previously in this post). Version 0.71 is downloadable from here.

If you use Putty, please update it to version 0.71. Thank you.

Security vulnerabilities fixed:

=======================

=======================
Nvidia Geforce Experience Software:
=======================
In late March , Nvidia released a security advisory for their Geforce Experience software for Windows. This update resolves 1 high severity vulnerabilities (as per their CVSS base scores). The necessary updates can be applied by opening Geforce Experience which will automatically updated it or the update can be obtained from here.

=======================
GOG Galaxy
=======================
Golden Old Games (GOG) has published an update for their popular game distribution platform GOG Galaxy. It resolves 2 critical vulnerabilities. Additionally, 2 high severity and 2x medium severity vulnerabilities were also resolved. These vulnerabilities are discussed in more detail in this Cisco Talos blog post and within this Kaspersky ThreatPost article. Please update GOG Galaxy to version 1.2.54.23 or later to resolve these vulnerabilities.

I don’t often post about vulnerabilities in gaming clients/gaming distribution clients but like any software; security updates can and are made available for them.

September 2018 Update Summary

=======================
Update: 11th September 2018:
=======================
Earlier today Microsoft and Adobe made available their scheduled updates. Microsoft resolved 61 vulnerabilities more formally known as CVEs (defined).

At the time of writing; there are known issues but with only the now commonly occurring Windows 7 NIC being an issue this month:

KB4457128

KB4457144

KB4458321

Further details are available in Microsoft’s update summary for September.

Adobe issued 2 updates today:

Adobe ColdFusion (priority 2, resolves 6x critical CVEs)
Adobe Flash (priority 2, resoles 1x CVE)

As per standard practice if you use any of the above Adobe software, please update it as soon as possible especially in the case of Flash. Updates for Google Chrome will be available shortly either via a browser update or their component updater.

You can monitor the availability of security updates for most your software from the following websites (among others) or use one of the utilities presented on this page:

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

https://www.us-cert.gov/

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

Microsoft Hyper-V (affects Windows 10 and Windows 8.1 (including Windows RT 8.1) and their Server equivalents)

Windows Task Scheduler (relating to a previous blog post)

Security advisory for “FragmentSmack” CVE-2018-5391

====================
Please install the remaining updates at your earliest convenience.

As usual; 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.

Please find below summaries of other notable updates released this month.

Thank you.

=======================
Original Post:
=======================
In advance of further updates being released by Microsoft and Adobe this month I wish to provide details of notable updates made available so far. I will update this post as more updates are distributed.

Thank you.

=======================
Mozilla Firefox:
=======================
In early September Mozilla made available updated versions of Firefox:

Firefox 62: Resolves 1x critical CVE (defined), 3x high CVEs, 2x moderate CVEs, 3x low CVEs

Firefox ESR 60.2 (Extended Support Release): Resolves 1x critical CVE, 2x high CVEs, 2x moderate CVEs and 1x low CVE.

Further discussion of the other features introduced by Firefox 62 is available here. In the future Firefox will block multiple trackers which will boost privacy for it’s users. Future versions will implement these changes.

In-depth details of the security issues resolved by these updates are available in the links above. Details of how to install updates for Firefox are here. If Firefox is your web browser of choice, if you have not already done so, please update it as soon as possible to resolve these security issues.

=======================
Google Chrome:
=======================
Last week Google released version 69 (specifically version 69.0.3497.81) of Chrome celebrating Chrome’s 10th anniversary. This version not only incorporates fixes for 40 vulnerabilities but also includes many more improvements. Among them are an improved password manager/form filler and a change in how secured (encrypted) webpages are indicated.

Google Chrome updates automatically and will apply the update the next time Chrome is closed and then re-opened. Chrome can also be updated immediately by clicking the Options button (it looks like 3 stacked small horizontal lines, sometimes called a “hamburger” button) in the upper right corner of the window and choosing “About Google Chrome” from the menu. Follow the prompt to Re-launch Chrome for the updates to take effect.

=======================
VMware
=======================
VMWare has issued a single security advisory so far in September:

Security advisory 1 (addresses 2 vulnerabilities of Low severity):

  • AirWatch Agent for iOS (A/W Agent)
  • VMware Content Locker for iOS (A/W Locker)

If you use the above VMware product, please review the security advisory and apply the necessary updates.

Vendors Respond to Foreshadow (L1TF) Vulnerabilities

Yesterday, academic and security researchers publically disclosed (defined) 3 new vulnerabilities affecting Intel CPUs (AMD and ARM are not affected).

What are these new vulnerabilities and what can they allow an attacker to do?
The first vulnerability known as Foreshadow or CVE-2018-3615 is used to extract data from an Intel SGX (Software Guard Extensions)(defined) secure enclave (area) by creating a shadow copy of the SGX protected data but that copy does not have the protection of SGX and can be read/accessed by the attacker. The attacker can also re-direct speculative execution into copying further private/sensitive into the shadow copied area while at the same time making it appear that area is genuine and thus has the same protection as the real SGX protected data.

The second vulnerability (part of a wider Foreshadow Next Generation (NG) group of two variants) known as CVE-2018-3620 allows the reading of data copied into the level 1 cache (defined) of a CPU (defined) when that data is in use by a computer operating system e.g. Red Hat Linux, Apple macOS or Microsoft Windows.

The third vulnerability is the second and final variant of the Foreshadow NG group known as CVE-2018-3646.  This affects virtualised environments. If a CPU thread (defined) being directed by an attacker is able to read the level 1 cache of a CPU that is also shared by another thread by a victim user (within another virtualised environment but using the same physical CPU) while that request will be blocked; if the information the attacker is looking to steal is in the level 1 cache they may still get a glimpse of this information.

How can I protect myself from these new vulnerabilities?
For the first and second vulnerabilities; the microcode (defined)/firmware (defined) updates made available earlier this year coupled with the newly released updates for operating systems linked to below will mitigate these two issues.

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For the third vulnerability; affecting virtualised (defined) environments there are operating system updates and microcode/firmware updates available that will occasionally clear the contents of the level 1 cache meaning that when the attacker attempts to read it they will not receive any benefit from doing so. Partially removing the usefulness of the cache will have a performance impact from a few percent up to 15 percent in the worst case scenario.

However to completely mitigate this third vulnerability a capability known as Core Scheduling needs to be leveraged. This ensures that only trusted/non attacker controlled virtual machines have access to the same thread (this capability is already available in some virtual machine (hypervisor)(defined) environments).

However in some environments if it cannot be guaranteed that all virtual machines are trustworthy the disabling of Intel Hyper Threading (this means that only 1 thread will work per CPU core)(otherwise known as simultaneous multi-threading (SMT)(defined)) may be necessary and will more significantly impact performance than just the level 1 cache clearing.

In summary for this third vulnerability; depending upon the virtualised environment you are using and the trustworthiness of the virtual machines you are using will determine how many of the these extra security measure you will need to take.

To be clear I am NOT advocating that Intel Hyper Threading/SMT be disabled EN MASSE for security reasons. As per the advice in the linked to advisories (below)(specifically Intel and VMware) ; you MAY wish to disable Intel Hyper Threading/SMT to mitigate the third vulnerability (CVE-2018-3646) depending upon the environment your virtualised machines are operating.

This Ars Technica article explains it very well: “if two virtual machines share a physical core, then the virtual machine using one logical core can potentially spy on the virtual machine using the other logical core. One option here is to disable hyperthreading on virtual-machine hosts. The other alternative is to ensure that virtual machines are bound to physical cores such that they don’t share.”

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Please find below links to vendor responses on these vulnerabilities as well as videos that can help in understanding these vulnerabilities:

Thank you.

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Foreshadow Vulnerability Official Website:
https://foreshadowattack.eu/

Intel’s Blog Post:
https://newsroom.intel.com/editorials/protecting-our-customers-through-lifecycle-security-threats/

Intel’s FAQ Page:
https://www.intel.com/content/www/us/en/architecture-and-technology/l1tf.html

Intel’s Security Advisory:
https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00161.html

Intel’s Software Developer Guidance:
https://software.intel.com/security-software-guidance/software-guidance/l1-terminal-fault

Red Hat’s Security Advisory:
https://access.redhat.com/security/vulnerabilities/L1TF

Linux Kernel Patch:
https://lore.kernel.org/patchwork/patch/974303/

Oracle’s Security Advisory:
https://blogs.oracle.com/oraclesecurity/intel-l1tf

Amazon Web Services’ Security Advisory:
https://aws.amazon.com/security/security-bulletins/AWS-2018-019/

Google Cloud Security’s Blog Post:
https://cloud.google.com/blog/products/gcp/protecting-against-the-new-l1tf-speculative-vulnerabilities

Microsoft Windows Azure’s Guidance:
https://docs.microsoft.com/en-us/azure/virtual-machines/windows/mitigate-se

Microsoft’s Windows Security Advisory (high level details):
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/ADV180018

Microsoft’s Technical Analysis of the Foreshadow Vulnerabilities:
https://blogs.technet.microsoft.com/srd/2018/08/10/analysis-and-mitigation-of-l1-terminal-fault-l1tf/

VMware Security Advisories:
https://www.vmware.com/security/advisories/VMSA-2018-0020.html

https://www.vmware.com/security/advisories/VMSA-2018-0021.html
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Videos:
Foreshadow Video (explains the first vulnerability very well):
https://www.youtube.com/watch?v=ynB1inl4G3c

Intel’s Video (explains all 3 vulnerabilities):
https://www.youtube.com/watch?v=n_pa2AisRUs

Demonstration of the Foreshadow attack:
https://www.youtube.com/watch?v=8ZF6kX6z7pM

Red Hat’s Video (explains all 3 vulnerabilities):
https://www.youtube.com/watch?v=kBOsVt0iXE4

Red Hat’s In-depth video of the 3 vulnerabilities:
https://www.youtube.com/watch?v=kqg8_KH2OIQ

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