Daily Archives: January 16, 2018

Responding to the Meltdown and Spectre Vulnerabilities

Please scroll down for more updates to this original post.
Update: 23rd May 2018:
For information on the Spectre NG vulnerabilities please refer to this new blog post

Thank you.

Original Post:
Earlier in January updates for Linux, Apple and Windows were made available to work towards addressing the 3 security vulnerabilities collectively known as Meltdown and Spectre.

Why should these vulnerabilities be considered important?
I’ll provide a brief summary of the two categories of vulnerabilities:

Meltdown (CVE-2017-5754): This is the name of the vulnerability discovered that when exploited by an attacker could allow an application running with standard privileges (not root or elevated privileges) to read memory only intended for access by the kernel.

Spectre (Variant 1: CVE-2017-5753 ; Variant 2: CVE-2017-5715): This is a category of two known vulnerabilities that erode the security boundaries that are present between applications running on a system. Exploitation can allow the gathering of information from applications which could include privileged information e.g. usernames, password and encryption keys etc. This issue can be exploited using a web browser (e.g. Apple Safari, Mozilla Firefox, Google Chrome, Microsoft Edge (or IE) by using it to record the current time at very short intervals. This would be used by an attacker to learn which memory addresses were cached (and which weren’t) allowing the attacker to read data from websites (violating the same-origin policy) or obtain data from the browser.

Browser vendors have responded by reducing the precision of JavaScript timing and making it more unpredictable while other aspects of JavaScript timing (using the SharedArrayBuffer feature) have been disabled.

More in-depth (while still being less technical) descriptions of these issues are available here , here and here.

How can I protect myself from these vulnerabilities?
Since these vulnerabilities are due to the fundamental architecture/design of modern CPUs; it is not possible to fully address them. Instead a combination of software fixes and microcode updates (defined) is more a viable alternative than re-designing the established architecture of modern CPUs.

In-depth lists of updates available from multiple vendors are available here and here. I would suggest glancing at the affected vendors and if you own a device/product from them; checking if you are affected by these vulnerabilities. A list of BIOS (defined) updates from multiple vendors are available here. Google Chrome has a Site Isolation mode that can mitigate these vulnerabilities which will be more comprehensively addressed in Chrome version 64 scheduled for release last this month.

At this time my systems required updates from Google, Mozilla, Microsoft, Apple, VMware, Asus, Lenovo and Nvidia. Many of many existing desktops are unlikely to receive microcode and BIOS updates due to be more than 3 years old. However my Windows 10 laptop has received a BIOS update from the manufacturer.

Are there disadvantages to installing these updates?
While these updates increase security against these vulnerabilities; performance issues and stability issues (Intel and AMD) after the installation of these updates have been reported. These vary in severity but according to Intel and Microsoft the updates will be refined/optimised over time.

Benchmarks (for desktops) made available by TechSpot show negligible impact on most tasks that would stress a CPU (defined). However any work that you perform which makes of large files e.g. databases may be significantly impacted by the performance impact these updates have when accessing files on disk (mechanical and solid state). For laptops the slowdown was felt across almost all workload types. Newer and older silicon were inconsistently impacted. At times even some Intel 8th generation CPUs were impacted more than 5th generation CPUs.

Details of the anticipated performance impact for Linux, Apple macOS (and iOS) and Windows are linked to. Further reports of reduced performance from Intel and Apple devices have also been recorded. Further details of a feature known as PCID (Process-Context Identifiers) within more recent CPUs which will help reduce the performance impact are provided here. For Intel CPUs, 4th generation Core CPUs and later should include it but any CPU manufactured after 2011 should have it (one of my CPUs; a Core i7 2600K has this feature, verified using Sysinternals Coreinfo). A full list of Intel CPUs affected by these vulnerabilities is here.

With the widely reported stability and performance issues present it is your decision if you install the necessary updates now or wait until further refinements. If you experience issues, please report them to the manufacturers where possible and within online forums if not. More refined updates will only be created if a need to do so is established.

I’m in the process of updating my systems but will benchmark them before and after each updates to determine an impact and make a longer term decision to keep the updates or uninstall them until further versions become available. I’ll update this post as I gather more results.

Update: 16th January 2018:
A newly released free utility from Gibson Research (the same website/author as the well-known ShieldsUp firewall tester) named InSpectre can check if your Windows system has been patched against Meltdown and Spectre and can give an indication of how much the performance of your system will be affected by installing and enabling the Windows and/or the BIOS updates.

Please note: I haven’t tried this utility yet but will this weekend (it will help with the tests I’m carrying out (mentioned above). I’ll update this post when I have tried out this utility.

Thanks again.

Update: 24th January 2018:
As promised I gathered some early results from a selection of CPUs and the results for all but recent CPUs are evidence they will experience a potentially noticeable performance drop:

CPUs supporting PCID (obtained using Sysinternals Coreinfo):
Intel Core i7 Extreme 980X @ 3.33 GHz
Intel Core i7 2600K @ 3.8 GHz
Intel Core i5 4590T @ 3.3 GHz
Intel Core i7 6500U (laptop CPU) @ 2.5 GHZ

CPUs supporting INVPCID (obtained using Sysinternals Coreinfo):
Intel Core i5 4590T @ 3.3 GHz
Intel Core i7 6500U (laptop CPU) @ 2.5 GHZ

Explanations of the purpose and relevance of the PCID and INVPCID CPU instructions are available from this Ars Technica article. The results from InSpectre only show positive results when both PCID and INVPCID are present backing up the observations within the above linked to Ars Technica article (that the updates take advantage of the performance advantages of these instructions when both are present).

The results from InSpectre back up these findings by stating that the 980X and 2600K will not deliver high performance protection from Meltdown or Spectre. Since my PCs are mainly used for more CPU intensive tasks (rather than disk intensive) e.g. games and Folding@Home; I still don’t expect too much of a performance decrease. The older CPUs are due for replacement.

You may ask; “why am I so concerned with the performance impact of these updates?” The answer is that significant time and investment has been made into the above systems for them to perform at peak performance for the intended tasks I use them for. Performance and security are both very important to me and I believe there should only be a small trade off in performance for better security.

My next step will be to benchmark the CPU, hard disk and GPU of each system before and after installing each update. I will initially do this for the 6500U and 2600K systems and provide these results. The categories of updates are listed below. I will keep you informed of my findings.

Thank you.
Update 1: Software updates from Microsoft for Meltdown and Spectre
Update 2: Firmware update (where available)
Update 3: Nvidia / AMD GPU driver update

Update: 13th February 2018:
Sorry for the long delay (I was travelling again for my work). The above benchmarking is now taking place and I will make the results available as soon as possible. Thanks for your understanding.

Update: 27th February 2018
Earlier last week Intel made available further microcode updates for more CPUs. These updates seek to address variant 2 of the Spectre vulnerability (CVE-2017-5715). Updates are now available for the CPUs listed below.

As before, please refer to the manufacturer of your motherboard of your system for servers, desktops and laptops or the motherboard manufacturer for any custom built systems you may have to determine if these updates have been made available for your specific systems. Further information for corporate system administrators containing details of the patching process is available within this link (PDF):

  • Kaby Lake (Intel 7th Generation Core CPUs)
  • Coffee Lake (Intel 8th Generation Core CPUs)
  • Further Skylake CPUs (Intel 6th Generation Core CPUs)
  • Intel Core X series (Intel Core i9 CPUs e.g. in the 7900 and 7800 model range)
  • Intel Xeon Scalable (primarily targeted at data centres)
  • Intel Xeon D (primarily targeted at data centres)

Information on patches now available for OpenBSD and FreeBSD are located within the following links:

OpenBSD mailing list
The Register: OpenBSD Patch now Available

FreeBSD Wiki
Softpedia: Spectre and Meltdown mitigations now available

Update: 1st April 2018
As vendors have responded to these vulnerabilities; updates have been released for many products. I will describe these updates in more detail below. Apologies if I have omitted any, this isn’t intentional but the list below should still be useful to you:

Google ChromeOS:
Following the release of ChromeOS 64 in February which provided updates against the Meltdown and Spectre vulnerabilities, ChromeOS 65 includes further mitigations against these vulnerabilities including the more efficient Retpoline mitigation for Spectre variant 2.

Sony Xperia:
In late February Sony made available updates which include mitigations for Meltdown and Spectre for their Xperia X and Xperia X Compact phones which brings the build number to 34.4.A.2.19

Microsoft Issues Microcode Updates:
As previously mentioned when this blog post was first published; updates for the Meltdown and Spectre vulnerabilities are made up of software updates, microcode updates and firmware (BIOS updates) and GPU drivers.

Due to the complexity of updating the firmware of computer systems which is very specific and potentially error prone (if you apply the wrong update to your device it can render it useless, meaning it will need to be repaired/replaced (which is not always possible) Microsoft in early March began to issue microcode driver updates (as VMware describes they can be used as substitutes for firmware updates). Microcode updates have been issued in the past to address CPU reliability issues when used with Windows.

Intel Firmware Updates:
As with previous microcode updates issued by Intel in late February; these updates seek to resolve variant 2 of the Spectre vulnerability (CVE-2017-5715).

While Intel has issued these updates; they will be made available separately by the manufacturer of your motherboard of your system for servers, desktops and laptops or the motherboard manufacturer for any custom built systems you may have. You will have to determine from the updates those vendors issue if they are available for the products that you own.

Unfortunately not all systems will receive these updates e.g. most recent system was assembled in 2014 and has not received any updates from the vendor; the vendor has issued updates on their more recent motherboards. Only my 2016 laptop was updated. This means that for me; replacing the systems gradually is the only means of addressing variant 2 of the Spectre vulnerability.

Intel’s updates are for the Broadwell (5th generation CPUs i.e. 5000 series) and Haswell (4th generation CPUs i.e. 4000 series).

Microsoft Surface Pro:
Earlier this week Microsoft released firmware updates for their Surface Pro which mitigate the Meltdown and Spectre vulnerabilities. This link provides further details and how to install the updates.

Microsoft Issues Further Security Update on the 29th March:
As noted in my separate post; please refer to that post for details of a security update for Windows 7 SP1 64 bit and Windows Server 2008 R2 SP1 64 bit that resolve a regression (an un-intentional coding error resulting in a previously working software feature no longer working, alternative definition here) which introduced an additional elevation of privilege (defined) security vulnerability in the kernel (defined) of those Windows versions.

Microsoft Offers Bug Bounty for Meltdown and Spectre vulnerabilities:
Microsoft have announced bug bounties from $5000 to $250,000 to security researchers who can locate and provide details of exploits for these vulnerabilities upon Windows, Azure and Microsoft Edge.

If such a programme is successful it could prevent another instance of needing to patch further related vulnerabilities after the issues have been publicly disclosed (defined). This is sure to assist the system administrators of large organisations who currently in the process of deploying the existing updates or who may be testing systems on a phased basis to ensure performance is not compromised too much.

Further details are available from this link.

Update: 6th April 2018
Earlier this week, Intel issued a further progress update for the deployment of further microcode for their CPUs.

A further 5 families of CPUs have now completed testing and microcode updates are available. These families are:

    • Arrandale
    • Clarkdale
    • Lynnfield
    • Nehalem
    • Westmere

However a further 9 families will not receive such updates for the reasons listed below. Those families are:

      • Micro-architectural characteristics that preclude a practical implementation of features mitigating [Spectre] Variant 2 (CVE-2017-5715)
      • Limited Commercially Available System Software support
      • Based on customer inputs, most of these products are implemented as “closed systems” and therefore are expected to have a lower likelihood of exposure to these vulnerabilities.


      • Bloomfield
      • Clarksfield
      • Gulftown
      • Harpertown Xeon
      • Jasper Forest
      • Penryn
      • SoFIA 3GR
      • Wolfdale
      • Yorkfield

This announcement from Intel means my Intel Core i7 Extreme 980X (from 2010) won’t receive an update. This system isn’t used very much on the internet and so the impact is limited. I am hoping to replace this system in the near future too.


Please review the updated PDF made available by Intel (I can upload the PDF to this blog if Intel place it behind an account which requires sign in. At this time the PDF link still works).

As before; please monitor the websites for the manufacturer of your system for servers, desktops and laptops or the motherboard manufacturer for any custom built systems you may have to determine if these updates have been made available for your specific systems.

Thank you.

BranchScope Vulnerability Disclosed:
In a related story; four security researchers from different universities responsibly disclosed (defined) a new side channel attack affecting Intel CPUs. This attack has the potential to obtain sensitive information from vulnerable systems (a similar result from the existing Meltdown and Spectre vulnerabilities).

Further details of this attack named “BranchScope” are available in this Softpedia article and this paper from the researchers. Within the above article Intel responded to this attack stating that this vulnerability is similar to known side channel and existing software mitigations (defined) are effective against this vulnerability. Their precise wording is provided below.

Thank you.

An Intel spokesperson has provided the following statement:

“We have been working with these researchers and have determined the method they describe is similar to previously known side channel exploits. We anticipate that existing software mitigations for previously known side channel exploits, such as the use of side channel resistant cryptography, will be similarly effective against the method described in this paper. We believe close partnership with the research community is one of the best ways to protect customers and their data, and we are appreciative of the work from these researchers.”

Update: 13th April 2018
AMD have issued microcode (defined) updates for Windows 10 Version 1709 to enhance the protection of their customer’s against variant 2 (CVE-2017-5715) of the Spectre vulnerability. Further details of these updates are available within these KB articles: KB4093112 and KB3073119

Thank you.

Update: 18th May 2018
Please refer to the beginning of the May and April security update summaries for further updates related to addressing Spectre variant 2 (v2).


January 2018 Update Summary

Update: 31st January 2018:
Please scroll down in this post to view more recent software updates available since the original posting date of the 16th of January 2018. Thank you.

Last Tuesday Microsoft released their routine security updates to address 56 vulnerabilities more formally known as CVEs (defined). Further details are provided within Microsoft’s Security Updates Guide.

This month there are 11 knowledge base articles detailing potential issues (many of which are pending resolutions) you may experience upon installing these updates. They are listed below for your reference:













Separately Adobe released Flash Player v28.0.0.137 to address a single priority 2 CVE.

As always; you can monitor the availability of security updates for most your software from the following websites (among others) or use Secunia PSI:
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 January’s Microsoft updates, I will prioritize the order of installation below. I will discuss this month’s out of band (outside of the regular schedule) patches for Meltdown and Spectre in a separate blog post; the relevant CVEs are still listed below. A useful list of all CVEs for this month is present here:

CVE-2017-5753 – Bounds check bypass (known as Spectre Variant 1)

CVE-2017-5715 – Branch target injection (known as Spectre Variant 2)

CVE-2017-5754 – Rogue data cache load (known as Meltdown Variant 3)

CVE-2018-0802: Microsoft Office zero day (similar to Novembers Office equation editor vulnerability)

Microsoft Office (18 further CVEs)

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


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.

For this month; please take extra care with your back up to ensure you can restore your systems should you wish to revert your systems prior to installing the Meltdown and Spectre patches should you wish to uninstall the Security only bundle of updates or the updates are causing your system to become unstable.

Thank you.

Wireshark 2.4.4 and 2.2.12
v2.4.4: 3 CVEs (defined) resolved

v2.2.12: 4 CVEs resolved

As per standard process Linux distributions can obtain this update using the operating systems standard package manager (if the latest version is not installed automatically using the package manager you can instead compile the source code (v2.4.4) or v2.2.12). This forum thread and this forum thread may also be helpful to you with installing Wireshark on your Linux based system.

For Mac OS X and Windows, the update is available within the downloads section of the Wireshark website. In addition, a detailed FAQ for Wireshark is available here.

Update: 24th January:
Oracle have resolved 237 vulnerabilities with the security updates they have made available this month. Further details and installation steps are available here. Within the 237 vulnerabilities addressed, 21 vulnerabilities were addressed in the Java runtime. 18 of these 21 are remotely exploitable without an attacker needing to obtain a user’s username and password (their credentials).

If you use any of the Oracle products listed here, please install the appropriate security updates as soon as possible.

Particular priority should be given to Oracle WebLogic Server and PeopleSoft due to documented incidents of attackers using such installations for crypto currency mining with one such incident resulting in more than USD $226,000 being mined. Further details are available in the following blog post from security vendor Onapsis.

Further updates released in January:
VMware Updates:
In early January; VMware issued security updates to address the Meltdown and Spectre vulnerabilities within some of their products. Another advisory  was also released later in January. The affected products/appliances are listed below. For virtual machines used with VMware Fusion and VMware Workstation, the steps listed within this knowledge base article should also be followed.

Please review the above linked to security advisories and knowledge base article and apply the necessary updates and mitigation steps.

Affected products/appliances:

  • VMware vCenter Server (VC)
  • VMware vSphere ESXi (ESXi)
  • VMware Workstation Pro / Player (Workstation)
  • VMware Fusion Pro / Fusion (Fusion)

Mozilla Firefox:
In January Mozilla issued security updates for Firefox and Firefox ESR (Extended Support Release):

Firefox 57.0.4 (2 mitigations added)

Firefox 58: 3x critical, 13x high, 13x moderate, 2x low CVEs

Firefox 58.0.1: 1x critical CVE

Firefox ESR 52.6: 1 high CVE

Firefox ESR 52.6: 2x critical, 8x high, 1x moderate

Further 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:
In late January an update for Google Chrome was made available which included 53 security fixes.

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.

In late January a security researcher located 2 vulnerabilities within 7-Zip. He reported them to the developer Igor Pavlov who very quickly released an updated version; v18.00 Beta. This has since been updated to 18.01 Stable to fix further issues (NOT security related).

The alternative Windows file manager Directory Opus will include the updated 7-Zip DLL (defined) within their next release. Their current beta already contains these fixes.

While 7-Zip does not have many vulnerabilities discovered within it (which has both advantages and disadvantages), there appears to be an increasing emphasis on it since it is used by anti-malware software and other applications e.g. VMware Workstation. Thus when a security update is issued; all of this software should eventually include the fixes. This occurred last year with the release of 7-Zip 16.00 to resolve 2 other security vulnerabilities.

Separately, Malwarebytes updated their Anti-Malware product to version 3.4.4 to update the 7-Zip DLL (defined) within it. Further details are available in my March 2018 Update Summary blog post.

If you use 7-Zip, please ensure it is updated to resolve both this year’s vulnerabilities and last year’s vulnerabilities (if you hadn’t already installed version 16 or later). Please also update Malwarebytes Anti-Malware or Directory Opus if you use them.

Nvidia Geforce Drivers:
This driver update applies to Linux, FreeBSD, Solaris and Windows and mitigates the Meltdown security vulnerability (CVE-2017-5753). While Nvidia’s GPUs are not vulnerable to Meltdown or Spectre, the GPUs interaction with an affected CPU has the potential for exploitation.The steps to install the drivers are detailed here. I detailed where Nvidia list their security advisories in a previous blog post. More details about the Meltdown and Spectre vulnerabilities are available in this blog post.

Hitman Pro:
As recommended on my Tools and Resources page, Hitman Pro (now part of Sophos Security) has been updated to version 3.8.20 (Build 292). This update resolves 2 vulnerabilities relating to libraries (defined) the tool uses namely zlib and libpng. Any previous version of the tool should update automatically when opened to the most recent version.

Adobe Flash Player 2018 Update Tracker

Just like the 2015 and 2016 tracker  and 2017 trackers that are incredibly popular on this blog; I am providing the same information below for the year 2018.

I have created a new post to make the timeline easier to follow. As before it will be updated throughout the year with any details of the Flash vulnerabilities being exploited.

Thank you.


9th January: Adobe releases Flash Player v28.0.0.137 resolving 1x priority 2 CVE (defined).

6th February: Adobe releases Flash Player v28.0.0.161 resolving 2x priority 1 CVEs. Please see the timeline update for the 13th of April (below) for more information on how one of these vulnerabilities is now being exploited.

13th March: Adobe releases Flash Player v29.0.0.113 resolving 2x priority 2 CVEs.

10th April: Adobe releases Flash Player v29.0.0.140 resolving 6x priority 2 CVEs.

8th May 2018: Adobe releases Flash Player v29.0.0.171 resolving 1x priority 2 CVE.

7th June 2018: Adobe releases Flash Player v30.0.0.113 resolving 4x CVEs with an overall priority of 1.

10th July 2018: Adobe releases Flash Player v30.0.0.134 resolving 2x CVEs with an overall priority of 2.

14th August 2018: Adobe releases Flash Player v30.0.0.154 addressing 5x CVEs with an overall priority of 2.

11th September 2018: Adobe releases Flash Player v31.0.0.108 addressing 1x CVE with an overall priority of 2.

14th November 2018: Adobe releases Flash Player v31.0.0.148 addressing 1x priority 2 CVE.

5th December 2018: Adobe releases Flash Player v32.0.0.101 addressing 2x priority 1 CVEs. CVE-2018-15982 was being exploited by an APT group.

Update: 10th January 2018: The timeline was updated to add the Adobe Flash Player update for January 2018. At the time of writing no exploits for the issue fixed by this update are known to be taking place.

Update: 13th February 2018: The timeline was updated to add the Adobe Flash Player update for February. One of these vulnerabilities CVE-2018-2878 is a zero day (defined) vulnerability being exploited in targeted attacks.

Update: 13th March 2018: The timeline was updated to add the Adobe Flash Player update for March. At the time of writing neither of the 2 vulnerabilities fixed are being exploited.

Update 1st April 2018: No further vulnerabilities within Flash Player were disclosed during the Pwn2Own 2018 competition.

Update 13th April 2018: The timeline was updated to add the Adobe Flash Player update for April. At the time of writing none of the 6 vulnerabilities fixed are being exploited.

Update 8th May 2018: The timeline was updated to add the Adobe Flash Player update for May. Similar to April; at the time of writing the resolved vulnerability is not being exploited.

CVE-2018-4878; the use after free (defined) vulnerability resolved by Adobe in February is now being used by the ThreadKit exploit key (defined) to send Microsoft Office documents exploiting this flaw. Please update Adobe Flash Player if you have it installed and do not open any document attached to an email you weren’t expecting. Further details are available in this news article.

Update: 12th June 2018: The timeline was updated to add the Adobe Flash Player update for June. This was released ahead of schedule on the 7th of June. This update resolved a zero day vulnerability (defined) CVE-2018-5002 which required little to no user interaction to trigger. Further details are available in my separate blog post.

Update: 27th July 2018: A US Senator has asked for 3 government agencies to cease using Adobe Flash by August 2019 in advance of the deadline set by Adobe for of the end of year 2020. The timeline was also updated to include the Adobe Flash Player update for July.

Update 23rd August 2018: The timeline was updated to add the Adobe Flash Player update for August. At the time of writing none of the 5 addressed vulnerabilities are being exploited.

Update 9th October 2018: The timeline was updated to add the Adobe Flash Player update for September (sorry for the delay). At the time of writing the addressed vulnerability is not being exploited. No updates for October 2018 have been issued.

Update 14th November 2018: The timeline was updated to add the Adobe Flash Player update for November. At the time of writing the addressed vulnerability is not being exploited. No updates for October 2018 were issued.

Update: 11th December 2018: The timeline was updated to add the Adobe Flash Player update for December. Further details of how the patched vulnerability CVE-2018-15982 were used in an APT attack is linked to above. Thank you.