plc.myforum.ro

mark11 · Member Joined: 30 Mar 2014 Posts: 114

Understanding Meltdown & Spectre: What To Know About New Exploits That Affect Virtually All CPUs

Understanding Meltdown & Spectre Understanding Meltdown & Spectre

Both Meltdown and Spectre are local attacks that require executing malicious code on a target machine. This means that these attacks are not (directly) remote code execution attacks – think Nimda or Code Red – and that systems cannot be attacked merely by being connected to a network. Conceptually, these are closer to privilege escalation attacks, a class of attacks that help you get deeper into a system you already have access to. With that said however, researchers have shown that they can perform Spectre-based attacks using JavaScript, so it is possible for a web browser to pull a malicious JavaScript file and then attack itself in that fashion.

Along with not directly being remotely exploitable, even if Meltdown and Spectre attacks are executed on a local system, the nature of the exploit is that these are read-only attacks. That is, they can only read information from a system. They cannot directly force code execution in the OS kernel, in other virtual machines, or other programs. These sort of information disclosure attacks can still be devastating depending on what information is leaked – and there is always the risk of using that information to then chain it into a code execution attack – which is why they’re still concerning. But the real risk is in hostile parties using these attacks to steal information, not to control a system.

Meltdown and Spectre can be mitigated in software: Because the root issues at the heart of Meltdown and Spectre are at the hardware level, ideally, that hardware needs to be replaced. As replacing 20 years of systems isn’t remotely practical however, like other CPU errata it can be mitigated in a combination of CPU microcode and operating system updates. Vendors like Microsoft, Apple, and the Linux distros are already in the process of rolling out some of these fixes, including an ultra-rare out of band security update from Microsoft Wednesday evening.

Understanding Meltdown & Spectre Understanding Meltdown & Spectre

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/ADV180002
https://portal.msrc.microsoft.com/en-US/eula
https://portal.msrc.microsoft.com/en-us/security-guidance/releasenotedetail/858123b8-25ca-e711-a957-000d3a33cf99

It’s a bad week to be Intel: Intel has been the dominant CPU supplier for cloud service providers, whom in turn are at the greatest risk from Meltdown and Spectre. Coupled with the fact that Intel is far more broadly affected by the more pressing Meltdown attack than any other vendor, and this means that Intel’s high margin server customers are shouldering the brunt of the risk of these attacks. And that in turn reflects poorly on Intel.

Read more:
https://www.anandtech.com/show/12214/understanding-meltdown-and-spectre

The big problem is if the producers Intel, AMD... did know this from the start or has been discovered by accident?????

Read also on this subject:
Meltdown and Spectre: ‘worst ever’ CPU bugs affect virtually all omputers
https://www.theguardian.com/technology/2018/jan/04/meltdown-spectre-worst-cpu-bugs-ever-found-affect-computers-intel-processors-security-flaw
Kernel panic! What are Meltdown and Spectre, the bugs affecting nearly every computer and device?
https://techcrunch.com/2018/01/03/kernel-panic-what-are-meltdown-and-spectre-the-bugs-affecting-nearly-every-computer-and-device/
Keep in touch about this...!!!!

Only Intel machines are affected by Meltdown
https://www.theverge.com/2018/1/4/16848976/how-to-protect-windows-pc-meltdown-security-flaw