CLD-411 Details

Other IDs this deficiency may be known by:

Basic Information:

Version Specific Information:

Details:

==================================== Edit #1 ===================================

Tue May 22 23:22:37 EDT 2018:
Version 4.9.102 of the Linux kernel has enabled the ability to mitigate against
this vulnerability. An updated kernel is not sufficient to mitigate this on its
own, but it is a necessary means to do so. Both an updated kernel and updated
CPU microcode are necessary to mitigate this vulnerability. As of this edit, we
are waiting for Intel to publish a microcode update.

=================================== Overview ===================================

From
https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00115.html:

CVE-2018-3639 - Speculative Store Bypass (SSB) - also known as Variant 4

Systems with microprocessors utilizing speculative execution and speculative
execution of memory reads before the addresses of all prior memory writes are
known may allow unauthorized disclosure of information to an attacker with
local user access via a side-channel analysis.

4.3 Medium CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N

================================ Initial Report ================================

The original report can be found at:
https://www.intel.com/content/www/us/en/architecture-and-technology/facts-about-side-channel-analysis-and-intel-products.html

The full white paper can be found at:
https://software.intel.com/sites/default/files/managed/b9/f9/336983-Intel-Analysis-of-Speculative-Execution-Side-Channels-White-Paper.pdf

The reports are too long to post here.

================================= Our Analysis =================================

See our blog post for additional information:
https://sourceforge.net/p/cucumber-linux/blog/2018/05/here-we-go-again-spectre-v3a-cve-2018-3640-and-spectre-v4-cve-2018-3639/

----- Affected Products -----
All versions of the 4.9 series Linux kernel up to and including 4.9.101 are
vulnerable to this. As of this writing (Tue May 22 12:39:14 EDT 2018), 4.9.101
is the latest 4.9 release available; future releases may or may not be
affected.

The Linux kernel as originally packaged on both Cucumber Linux 1.0 and 1.1 is
vulnerable.

----- Scope and Impact of this Vulnerability -----
The full impact of this vulnerability has not been sufficiently verified yet;
however, Intel has indicated that it "may allow unauthorized disclosure of
information to an attacker with local user access."

----- Fix for this Vulnerability -----
As of Tue May 22 12:39:14 EDT 2018, there are no publicly available fixes for
this vulnerability.

================================= Our Solution =================================

We are waiting for the upstream kernel developers and Intel to publish patches.