Tag Archives: Linux

Mitigating the Intel SWAPGS Vulnerability

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TL DR
This is medium severity information disclosure vulnerability. An attacker must already have compromised a system to exploit it. Patches from Red Hat, Google and Microsoft are available. Apple hardware does not appear to be affected.
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If we look back 2 weeks we saw the disclosure of a vulnerability relating to VideoLAN VLC being performed incorrectly. This week there is an example of how responsible disclosure should be carried out and demonstrates it can work very well.

Red Hat Linux, Google and Microsoft have all issued patches for a newly discovered variant of the original Spectre v1 vulnerability (initially disclosed in January 2018).

The performance impact of the updates is described in the Red Hat advisory in more detail:

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The fix for this CVE has shown to cause a minimal performance impact. The impact will be felt more in applications with high rates of user-kernel-user space transitions. For example, in system calls, NMIs, and kernel interrupts.

Early benchmarks for this mitigation show approximately 1% performance penalty:

https://www.phoronix.com/scan.php?page=article&item=swapgs-spectre-impact&num=1
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How does this vulnerability work?
When building a memory address to access computer make use of segment registers (CS, DS, SS, ES, FS, GS). The FS and GS registers are used when the CPU (defined) is in 64-bit mode. The SWAPGS instruction is used on 64-bit entry into kernel code to swap the current user space value of GS with the value intended to be used during kernel operations. GS is used to access kernel data, but it does not validate the values it uses. There are checks during instruction execution to check if a swap to kernel mode is necessary. It is possible for the speculative execution process (attempting to look ahead to improve performance) to mis-judge if a swap is necessary  resulting in a small window of time where the wrong GS is used for memory access leading to disclosure of privileged information.

How can I protect my organisation and myself from this vulnerability?
Earlier this week Red Hat and Google released updates to resolve this vulnerability. Microsoft issued their update silently on 9th July:

Red Hat Linux
https://access.redhat.com/articles/4329821

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=18ec54fdd6d18d92025af097cd042a75cf0ea24c

Google Chrome OS
https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/1739575

Microsoft Windows
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-1125

Thank you.

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.

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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.
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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.

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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.

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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

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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.

Responding to the Intel Spoiler Vulnerability

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Updated: 20th March 2019
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TL DR:
The Intel Spoiler vulnerability is not as bad as predicted. Software developers should continue to use safer code development practices.

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After the disclosure earlier this month of this vulnerability Intel have provided further information on how it affects their microprocessors. They have clarified that the Spoiler exploit by itself does not reveal secret data and is not a speculative execution side channel method:

Other good news is that existing mitigations such as KPTI (kernel page table isolation) reduce the risk of leaking data across privilege levels. They again confirmed that side channel safe software development practices such as “ensuring execution time and control flows are identical regardless of secret data” will mitigate classic side channel methods enabled by the Spoiler exploit. Furthermore, they confirmed memory modules which are already mitigated against Rowhammer attacks remain protected against the Spoiler exploit.

Lastly AMD provided formal confirmation that their microprocessors are not vulnerable after preliminary findings suggested they weren’t vulnerable. AMD’s statement is available from this link.

Thank you.

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Original Post:
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Earlier this month a new vulnerability was disclosed in a research paper titled “Spoiler: Speculative load hazards boost Rowhammer and cache attacks”.

TL DR: Mitigating this newly disclosed vulnerability is the job of software developers to work around using safer code development practices. Mitigating this issue in hardware will take longer since current measures cause too much of a performance penalty.

Why should this vulnerability be considered important?
Using this new method; attackers are likely to find existing cache and memory Rowhammer attacks easier to carry out. In addition, JavaScript (defined) attacks which can take long periods of time may be shortened to mere seconds. The paper contains a cache prime and probe technique to leak sensitive data using JavaScript.

This Spoiler vulnerability can be used by attackers (who MUST have already compromised your system) to extract sensitive information from the systems memory (RAM). An attack does not require elevated privileges.

What CPUs (microprocessors / computer chips) are affected?
This vulnerability affects Intel processors only; first generation Intel Core (from early 2006) and later are affected. ARM and AMD processors are not affected. Any system with an Intel Core processor is affected regardless of the operating they are using namely Linux, Unix, Apple macOS and Windows can be all affected.

How does this vulnerability achieve the above results?
The security researchers who authored the paper found a vulnerability in the memory order buffer that can be used to gradually reveal information about the mappings of physical memory to non-privileged software processes (in other words; applications). This technique also affects virtual machine (VM) and sandboxed (defined) environments.

The technique works by understanding the relationship between virtual and physical memory by timing the speculative load and store operations to these areas while looking out for discrepancies which disclose the memory layout to you. With this information an attacker knows where to focus their efforts.

Intel’s proprietary implementation of the memory subsystem (memory disambiguation) is the root cause of the vulnerability. When a physical address conflict (the address/area is already in use) occurs, the algorithm leaks the access timings. The algorithm in the researcher’s words works as follows “Our algorithm, fills up the store buffer within the processors with addresses that have the same offset but they are in different virtual pages. Then, we issue a memory load that has the same offset similarly but from a different memory page and measure the time of the load. By iterating over a good number of virtual pages, the timing reveals information about the dependency resolution failures in multiple stages.”

How can this vulnerability be mitigated/patched?
This vulnerability lies within the memory disambiguation algorithm which won’t be trivial to resolve anytime soon. Since this vulnerability is not related to last years Spectre vulnerability; mitigations for that vulnerability don’t help here. Current Spoiler mitigations have too much of performance penalty. At this time, Intel has issued the following statement:

“Intel received notice of this research, and we expect that software can be protected against such issues by employing side channel safe development practices. This includes avoiding control flows that are dependent on the data of interest. We likewise expect that DRAM modules mitigated against Rowhammer style attacks remain protected. Protecting our customers and their data continues to be a critical priority for us and we appreciate the efforts of the security community for their ongoing research.”

The side channel safe development practices are linked to below:

Software Guidance for Security Advisories

Addressing Hardware Vulnerabilities

Thank you.

February 2019 Update Summary

Earlier today Microsoft made available 13 bulletins and 3 advisories resolving 74 vulnerabilities (more formally known as CVEs (defined)) respectively. As always more details are available from Microsoft’s monthly summary page.

Also today Adobe released scheduled updates for the products listed below addressing 75 CVEs in total:

Adobe Acrobat and Reader: 71x priority 2 CVEs resolved (43 of the 75 are Critical, the remainder are Important severity)

Adobe ColdFusion: 2x priority 2 CVEs resolved

Adobe Creative Cloud Desktop Application: 1x priority 3 CVE resolved

Adobe Flash Player: 1x priority 2 CVE resolved

If you use the affected Adobe products; due to the public disclosure (defined) of CVE-2019-7089 as a zero day (defined) vulnerability, please install the Adobe Acrobat and Reader updates first followed by Flash Player and the remaining updates. I provide more detail on the zero day vulnerability in a separate post.

As we are accustomed to Microsoft’s updates come with a long list of Known Issues that will be resolved in future updates or for which workarounds are provided. They are listed below for your reference:

4345836
4471391
4471392
4483452
4486996
4487017
4487020
4487026
4487044
4487052

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:

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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.

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For this month’s Microsoft updates, I will prioritize the order of installation below:
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Microsoft Edge and Internet Explorer (multiple versions of Edge and IE affected)

Microsoft GDI+

Scripting Engine (CVE-2019-0590 , CVE-2019-0591 , CVE-2019-0593 , CVE-2019-0640  ,
CVE-2019-0642
, CVE-2019-0648 , CVE-2019-0649  , CVE-2019-0651 , CVE-2019-0652 , CVE-2019-0655 , CVE-2019-0658)

Windows DHCP

Microsoft Exchange

Microsoft SharePoint and CVE-2019-0604

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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.

Thank you.

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Nvidia Graphics Drivers:
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8 security vulnerabilities with the most severe having a CVSS V3 (defined) base score of 8.8 have been resolved within Nvidia’s graphics card drivers (defined) in February. These vulnerabilities affect Linux FreeBSD, Solaris and Windows. The steps to install the drivers are detailed here (and here) for Ubuntu and here for Linux Mint. Windows install steps are located here. If you use affected Nvidia graphics card, please consider updating your drivers to the most recent available.

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7-Zip:
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In the 3rd week of February; 7-Zip version 19.00 was released. While it is not designated as a security update; the changes it contains appear to be security related. While 7-Zip is extremely popular as a standalone application; other software such as Malwarebytes Anti-Malware, VMware Workstation and Directory Opus (among many others) all make use of 7-Zip. Directory Opus version 12.2.2 Beta includes version 19.00 of the 7-Zip DLL.

If you use these software applications or 7-Zip by itself, please update these installed applications to benefit from these improvements.

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Changes:
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– Encryption strength for 7z archives was increased:
the size of random initialization vector was increased from 64-bit to 128-bit, and the pseudo-random number generator was improved.
– Some bugs were fixed.
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If you are using the standalone version and it’s older than version 19, please consider updating it.

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Mozilla Firefox
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In mid-February Mozilla issued updates for Firefox 65 and Firefox ESR (Extended Support Release) 60.5:

Firefox 65.0.1: Resolves 3x high CVEs (defined)

Firefox 60.5.1: Resolves 3x high CVEs

As always; 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 changes such as improvements to Netflix playback, color management on Apple macOS and resolving audio/video delays during WebRTC calls etc.

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Wireshark 3.0.0, 2.6.7 and 2.4.13
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v3.0.0: 0 security advisories (new features and benefits discussed here and here)

v2.6.7: 3 security advisories

v2.4.13: 3 security advisories

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 (v3.0.0, v2.6.6 or v2.4.12). 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.

Note: from this post onwards, I will only report on the most recent (v3.0) and previous branches (v2.6) of Wireshark.

Thank you.

Linux and Windows Address Page Cache Vulnerabilities

In early January security researchers located further vulnerabilities in how Windows and Linux operating systems use a memory page cache.

How severe are these vulnerabilities and what is their impact?
One of the co-authors of the academic paper disclosing these vulnerabilities described the work as mostly “a matter of academic interest” meaning that attackers are less likely to take advantage of these vulnerabilities.

Local attacks:
For the localised rather than remote variant of utilizing these vulnerabilities; the attacker must already have gained access to the victim system to read the target memory page. The attacker could do this by “[having a] malicious process on the operating system or when processes run in sandboxes that have shared files”.

Other actions an attacker could potentially carry out are:

• Cloning an open window and replacing the legitimate application window
• Gathering the root (Linux) or administrator (Windows) password

Remote attack:
To exploit the vulnerabilities remotely; the researchers leveraged “timing differences between memory and disk access, measured on a remote system, as a proxy for the required local information”. This was achieved by measuring the times when soft page faults (the page is erroneously mapped, with the help of a process that runs on a remote server) occurred. The researchers were successful in sending data covertly from an unprivileged malicious process within the victim system to a remote server fulfilling the role of a web server. They used a technique from previous research namely the NetSpectre attack to distinguish cache hits and misses over a network connection. This was successful on systems with mechanical hard drives (HDDs) and solid-state disks (SSDs). SSDs were more complex since the timing differences were smaller but the researchers compensated by using larger files to distinguish between cache hits and misses.

How can I protect my organization/myself from these vulnerabilities?
Since these vulnerabilities are more academic in nature; attackers are less likely to exploit them. Linus Torvalds has explained that the code to resolve this vulnerability has been checked in and is undergoing testing before being more widely rolled out. For Windows; Build 18305 of the upcoming Windows 19H1 (otherwise known as Version 1903) due for release in April 2019 contains fixes for these vulnerabilities. It is anticipated Microsoft will back-port this patch to earlier Windows versions.

In addition; the mitigations for the Spectre vulnerabilities from last year should address the remote attack vector using the NetSpectre attack method.

Why are there so many timing attacks being disclosed lately?
Since modern systems rely on timing for almost every component e.g. the CPU (internal caches and registers respond in nanoseconds (ns)), the memory/RAM (e.g. CAS latency), HDDs (measured in milliseconds (ms) e.g. 8.9 ms), SSDs (e.g. 0.05 ms , much faster) we are likely to continue to see further vulnerabilities disclosed as further scrutiny is applied to devices and architectures that have been in use for many years.

E.g. the affected code from Linux was timestamped in 2000 and stated that further revision should be carried out when more information was known. 19 years later we know more and are revising that code. It’s a similar situation with Windows where the revised code works to ensure low privilege processes can no longer access page cache information or shared cache information. As The Register points out; “something complex that’s just working can remain untouched for a very long time, lest someone breaks it” and is more likely to contain vulnerabilities since nobody has taken the time to look for what has been there for years.

Thank you.

Oracle VirtualBox Zero Day Disclosed

In early November a security researcher publicly disclosed (defined) a zero day (defined) vulnerability within Oracle’s VirtualBox virtualisation software.

How severe is this vulnerability?
In summary; this vulnerability is serious but it could have been worse. In order to exploit it, an attacker would first need to have obtained elevated privileges on your system; root (defined) in the case of Linux and administrator (defined) in the case of Windows. Using this privilege the attacker can leverage the exploit to escape from the confines of the virtual machine (VM)(defined) into the system which hosts the virtual machine (in other words; the system which houses the virtual machine within its physical infrastructure). Once outside of the virtual machine the attacker must then elevate their privileges again since breaking out of the VM only gives them user level/standard privileges and not elevated privileges in the physical system. Thus the attacker would then need to use a separate exploit for another vulnerability (not related to this VirtualBox flaw) to elevate their privileges again to become root/admin within the physical system.

Obviously; the consequences of exploiting this vulnerability on a shared service/cloud infrastructure system would be more serious since multiple users would be affected all at once and the further exploitation of the resulting host systems could potentially provide the attacker with control over all the virtual machines.

How can an attacker exploit this vulnerability?
VirtualBox makes use of the Intel Pro/1000 MT Desktop (82540EM) network adapter to provide an internet connection to the virtual machines it manages. The attacker must first turn off this adapter in the guest (virtualised) operating system. Once complete they can then load a custom Linux kernel module (LKM)(defined) (this does not require a reboot of the system). That custom LKM contains the exploit derived from the technical write up provided. That new LKM loads its own custom version of the Intel network adapter. Next the LKM exploits a buffer overflow (defined) vulnerability within the virtualised adapter to escape the guest operating system. The attack must then unload the custom LKM to re-enable the real Intel adapter to resume their access to the internet.

How can I protect myself from this vulnerability?
While this is a complex vulnerability to exploit (an attacker would need to chain exploits together in order to elevate their privilege on the host system after escaping the VM), the source code needed to do so is available in full from the researcher’s disclosure; increasing the risk of it being used by attackers.

At the time of writing; this vulnerability has not yet been patched by VirtualBox. It affects versions 5.2.20 and earlier when installed on Ubuntu version 16.04 and 18.04 x86-64 guests (Windows is believed to be affected too). While a patch is pending; you can change the network card type to PCnet or Para virtualised Network. If this isn’t an option available or convenient for you; you can an alternative to the NAT mode of operation for the network card.

Thank you.

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

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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