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Spectre/Meltdown Vulnerabilities: What You Need To Know

Ben Miller  |  January 24, 2018

On January 1st, 2018 Intel disclosed a critical alert around a large variety of Intel CPUs that allows an attacker to read memory belonging to other processes. Further details from Google Project Zero, Cyberus Technology private researcher Paul Kocher, and various universities surfaced January 3, including white papers. The vulnerabilities are named Spectre and Meltdown. The purpose of this blog post is to:

  • Help you understand the issue
  • Point you to trusted resources to explain it in more depth
  • Determine how you can protect yourself against it

What is the Issue?

Spectre has been assigned CVEs CVE-2017-5753 and CVE-2017-5715. Meltdown has been assigned CVE CVE-2017-5754. Some elements of Spectre, at least for the moment, cannot be mitigated in software.

This vulnerability was privately disclosed to Intel and operating system vendors, but security researchers working independently have developed proof of concept code. In a statement released on January 3, Intel stated it is working with AMD and ARM, as well as with major operating system vendors, on fixes.

Microsoft released emergency patches for supported versions of Windows on January 3, and is patching Azure on an accelerated schedule. Microsoft has not stated if end-of-life systems such as Windows Vista, Windows XP, and Windows Server 2003 will be included. Apple included fixes in macOS 10.13.2, and plans more fixes in macOS 10.13.3 by the end of the month. Google addressed the issue on Android and Chrome OS in its January 2018 security patch.

Potential Impact

This vulnerability can be potentially exploited to defeat ASLR and KPTI on affected systems and read memory contents belonging to other processes running on the machine. At this point, the most useful scenario for an attacker would be to use it to steal passwords, credit card numbers, or other sensitive but succinct data from memory. On desktops and laptops, it can be exploited remotely via JavaScript residing on a web page. It could also be used in cloud environments to cross over into other virtual machines and steal data belonging to other customers.

The patches for this flaw may prove to be unpopular due to early reports stating to expect performance hits ranging from 5-30 percent. Reports from the field indicate 20% is a more common worst-case scenario on database and web servers. On desktops, the performance impact generally is minimal.

What Should You Do

Having a complete inventory of IT systems is critical for addressing vulnerabilities such as this one, including hardware make and model, CPU architecture, and operating system.

Workstations and virtual machines in cloud environments, which have the greatest exposure to the outside world, should have the highest priority when deploying patches. ISG Data Center infrastructure systems are in the process of patching. Servers running on virtual infrastructure under your control will be harder to exploit.

There are some caveats to patching Windows for this vulnerability. A Microsoft article on compatibility issues between this patch and certain third-party antivirus solutions is included in the Supporting Information section at the end of this document. GuidePoint recommends you confirm with your antivirus vendor that its solution is compatible with Microsoft’s update for Spectre and Meltdown. Slowdowns, although initially overstated, still have the potential to occur. The effect on workstations will be minimal. Servers that perform heavy I/O, such as web servers and databases, will incur more significant performance hits.

References

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Ben Miller

Cloud Network Security Engineer at ISG Technology
Information systems specialist turned offensive security expert Ben Miller - a.k.a. 'Hacker Ben' - has secured, hacked and taught many of the security systems that businesses trust and use. He focuses on bringing his knowledge to the next generation of security concerns for ISG and their clients and has presented at security conferences such as ShowMeCon and Bsides on malware and security processes.
About

Information systems specialist turned offensive security expert Ben Miller - a.k.a. 'Hacker Ben' - has secured, hacked and taught many of the security systems that businesses trust and use. He focuses on bringing his knowledge to the next generation of security concerns for ISG and their clients and has presented at security conferences such as ShowMeCon and Bsides on malware and security processes.

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