CPU Bug Patches for ClearOS, ClearVM and ClearBOX

CPU Bug Patches for ClearOS, ClearVM and ClearBOX

05 Jan

By now you've heard of the Meltdown and the Spectre suite of flaws — three variants of attack vectors exist and their related vulnerabilities that affect all Intel and some AMD and ARM processors. These bugs are hardware bugs and affect servers, workstations, and some handheld devices. To be clear, this is a hardware bug but we are taking steps to mitigate the damage that can be done by the hardware flaws.


Starting today, all ClearOS 7 systems that are set to get automatic updates will begin to receive patches to help mitigate the risks associated with Meltdown and Spectre.

Please click on the URL below for instructions on how to determine the Kernel version of your system.


If your system report shows the version number listed below or higher,  your ClearOS system has received the needed patches for Meltdown and Spectre. You will need to be on the following version or later to have the patches that deal with Meltdown and Spectre:

ClearOS 7: 3.10.0-693.11.6.v7 or later

ClearOS 6: 2.6.32-696.18.7.v6 or later (note, as of this writing, this build in currently building and this number may change)

Because this patch makes significant changes to the kernel which cannot be updated in a dynamic way to the running kernel, you will need to schedule a system reboot during a maintenance window (or as soon as possible) for the patches to take full effect.


Because of the difficulty with upstream patch availability with ClearVM, users of ClearVM will be required to migrate to the newer version of ClearVM that will be released in the January/February timeframe. To ensure that this exploit cannot be executed on your ClearVM environment, please ensure that local access to the ClearVM node and any VMs running under ClearVM is isolated to trusted users. As an immediate workaround in critical environments or those that are exposed in ways in which this exploit can be implemented, users of ClearVM can migrate their virtual machines to ClearOS under KVM and libvirt for the time being. Users of ClearVM with support options from ClearCenter can get support with this path if immediate resolution is required before the general release of the next ClearVM platform.


The type 2 variant of these exploits may require updates to your firmware of ClearBOX. We are still in the process of analyzing whether ClearOS sufficiently covers the patching requirements all by itself or if there are specific hardware-related patches that are required. Please stay tuned, inquire in the forums, or contact ClearCenter if you have a qualifying and current support subscription with ClearCenter.

Looking Forward:

Intel and other hardware manufacturers are looking for ways to apply firmware updates that could also help mitigate risk, but ClearOS and other OS providers are working independently to help protect users of affected server, workstation, laptop, and tablet gear. It's important to know that Meltdown and Spectre are processor hardware-related bugs that can't be completely fixed by software patches. However, there are a number of ways software patches can minimize the risk associated with these exploits and ClearCenter is committed to doing everything we can to mitigate any potential damage from Meltdown and Spectre. We will continue to release additional patches in the future to further help reduce your exposure to Meltdown and Spectre.

Potential Impact on System Performance:

Because of the nature of these vulnerabilities, the patch to address Meltdown include methods that segment memory pages. The result is that all patched systems with the Meltdown vulnerability may see a decrease in performance. This issue impacts many platforms including all versions of Linux, MacOSX, and Windows. We expect ClearOS systems to see a 5% to 20%+ decrease in speeds related to operations dealing in non-user space of memory.

Our advice is to let the automatic patches update your system and take the performance hit. However If you are willing to take some risk, it is possible to bypass the system patches and not take the performance hit. More information will be provided in the Community Forums and in qualified support ticket responses for users adversely affected by this issue who are willing to go without the security protections of the patch.


If you have an included support package with ClearCenter and your system is negatively impacted by the fix, feel free to open a ticket related to your specific performance issue. For ClearOS Community and Home users with self support please visit this forum thread for advice on how to maximize performance.