News

Intel Reveals New ‘Variant 4’ Meltdown, Spectre Vulnerability, Promises Fix

A new variant of the Spectre CPU security vulnerability was disclosed on Monday by Intel, Google, and Microsoft. The design flaw affects millions of computers and mobile devices from a large number of manufacturers.

Security researchers identified two software analysis methods that, if used for malicious purposes, have the potential to improperly gather sensitive data from multiple types of computing devices with different vendors’ processors and operating systems.

Intel is committed to product and customer security and to coordinated disclosure. We worked closely with other technology companies and several operating system and system software vendors, developing an industry-wide approach to mitigate these issues promptly.

The new “Speculative Store Bypass” variant has been dubbed “Variant 4,” and is similar to Spectre, taking advantage of the speculative execution mechanism of a CPU to allow hackers to gain access to sensitive information. it affects a large number of the processors in Intel’s family of CPUs.

Description:

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

CVE-2018-3640 – Rogue System Register Read (RSRE) – also known as Variant 3a

  • Systems with microprocessors utilizing speculative execution and that perform speculative reads of system registers may allow unauthorized disclosure of system parameters 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

Affected products:

The following Intel-based platforms are potentially impacted by these issues. Intel may modify this list at a later time.

 Intel® Core™ i3 processor (45nm and 32nm)
Intel® Core™ i5 processor (45nm and 32nm)
Intel® Core™ i7 processor (45nm and 32nm)
Intel® Core™ M processor family (45nm and 32nm)
2nd generation Intel® Core™ processors
3rd generation Intel® Core™ processors
4th generation Intel® Core™ processors
5th generation Intel® Core™ processors
6th generation Intel® Core™ processors
7th generation Intel® Core™ processors
8th generation Intel® Core™ processors
Intel® Core™ X-series Processor Family for Intel® X99 platforms
Intel® Core™ X-series Processor Family for Intel® X299 platforms
Intel® Xeon® processor 3400 series
Intel® Xeon® processor 3600 series
Intel® Xeon® processor 5500 series
Intel® Xeon® processor 5600 series
Intel® Xeon® processor 6500 series
Intel® Xeon® processor 7500 series
Intel® Xeon® Processor E3 Family
Intel® Xeon® Processor E3 v2 Family
Intel® Xeon® Processor E3 v3 Family
Intel® Xeon® Processor E3 v4 Family
Intel® Xeon® Processor E3 v5 Family
Intel® Xeon® Processor E3 v6 Family
Intel® Xeon® Processor E5 Family
Intel® Xeon® Processor E5 v2 Family
Intel® Xeon® Processor E5 v3 Family
Intel® Xeon® Processor E5 v4 Family
Intel® Xeon® Processor E7 Family
Intel® Xeon® Processor E7 v2 Family
Intel® Xeon® Processor E7 v3 Family
Intel® Xeon® Processor E7 v4 Family
Intel® Xeon® Processor Scalable Family
Intel® Atom™ Processor C Series (C3308, C3338, C3508, C3538, C3558, C3708, C3750, C3758, C3808, C3830, C3850, C3858, C3950, C3955, C3958)
Intel® Atom™ Processor E Series
Intel® Atom™ Processor A Series
Intel® Atom™ Processor X Series (x5-E3930, x5-E3940, x7-E3950)
Intel® Atom™ Processor T Series (T5500, T5700)
Intel® Atom™ Processor Z Series
Intel® Celeron® Processor J Series (J3355, J3455, J4005, J4105)
Intel® Celeron® Processor N Series (N3450)
Intel® Pentium® Processor J Series (J4205)
Intel® Pentium® Processor N Series (N4000, N4100, N4200)
Intel® Pentium® Processor Silver Series (J5005, N5000)

Intel says the new vulnerability carries a “moderate” severity rating, as many of the exploits that it uses have already been addressed. The company says it will still release a full mitigation option to “prevent this method from being used in other ways.”

The Variant 4 mitigation is currently in beta form, and has been delivered to OEM system and software makers, and Intel will leave it up to those vendors as to whether they’ll implement the mitigation. There is a potential for performance issues of 2 – 8% if the new mitigation is applied.

This mitigation will be set to off-by-default, providing customers the choice of whether to enable it. We expect most industry software partners will likewise use the default-off option. In this configuration, we have observed no performance impact. If enabled, we’ve observed a performance impact of approximately 2 to 8 percent based on overall scores for benchmarks like SYSmark(R) 2014 SE and SPEC integer rate on client1 and server2 test systems.

The Spectre and Meltdown vulnerabilities affect all modern processors for Intel, ARM, and AMD. However, Intel has faced the brunt of the scrutiny over the flaws, due to its dominance in the processor market. While Apple’s iOS and Mac devices are both affected by the vulnerabilities and Apple has responded by patching the vulnerabilities in those operating systems.

Chris Hauk

Chris is a Senior Editor at Mactrast. He lives somewhere in the deep Southern part of America, and yes, he has to pump in both sunshine and the Internet.