Anybody want to talk about Dirty Cow?

Hi All,

How worried is everyone about the Dirty Cow Linux exploit? Has anybody experienced attacks yet?

From the research I've done it seems that the exploit is "reliable" (that is it works nearly every time on vulverable systems) which is not good news.

We all believe that Unix/Linux systems are so much more secure than Windows because they're not targeted in the same way.

Q: Anybody have up to date knowledge as to which distros have now been patched and which are still at risk?

Thanks,

Dennis.

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Firstly take a look here:-

dirtycow.github.io/dirtyc0w.c at master * dirtycow/dirtycow.github.io * GitHub

Next this one could be even worse as the user numbers are much more to be able to target...
Make sute you watch the video; free software anyone? OUCH!

Using Rowhammer bitflips to root Android phones is now a thing | Ars Technica

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Here's a news clip from the UK. (BBC Copyright acknowledged)

Users of the Linux operating system are being urged to update it to remove a "serious" bug that hackers could use to hijack systems.
Known as the Dirty Cow bug, the vulnerability has been present in many versions of Linux for almost a decade.
The warnings come as malicious hackers start exploiting it to take over vulnerable computers.
The vulnerability gets its name from the Linux sub-system, called Copy-On-Write or COW, in which it appears.
Updated versions of Linux that no longer suffer the bug are now being widely distributed. Millions of computers, including a majority of web servers, run Linux or one of its variants.

"The nature of the vulnerability lends itself to extremely reliable exploitation," Dan Rosenberg, a security researcher at Azimuth Security, told tech news site Ars Technica. He added that it was the "most serious" bug of its type ever found in Linux.
The vulnerability allows attackers to steadily increase the amount of control they can exert over a target system.
Security expert Graham Cluley said the bug was of a type that did not normally prompt action because they were less likely to be exploited. However, he said, Dirty Cow should be taken seriously because there was some evidence that it was being actively abused.
Attack code that capitalised on the weakly protected sub-system was captured by developer Phil Oester as it was used in an attempt to take over a server he runs.
Mr Oester told the V3 tech news site that the vulnerability was easy to use and was "almost certain" to be more widely used by cyberthieves.

The thing is that according to RedHat the attacker has to be a local user, which implies that you know the local user, with unprivileged access. It does not say whether that user is allowed to execute code loaded from an external source, e.g. USB memory stick...
As I am not a professional I must assume that standard users are NOT allowed only admin' staff.

CVE-2016-5195 - Red Hat Customer Portal

However, and to me this is a big however, the Rowhammer _bug_ is much more serious as it can be buried inside a """free""" app' that could be DLed from so-called reputable sources and be stealthily called or installed inside what looks like a _cool_ app'. NASTY!

As we all know race conditions occur all the time in both HW and/or SW.
I had the condition(s) on both the AMIGA1200 and PC parallel ports when accessing HW I built many years ago so I am aware of situations like this. Obviously these were not OS crippling events but they taught me a lot and to research more about the situation.

Current technology is frighteningly quick compared to those units of yesteryear so even nanoseconds can be the breakpoint of today's HW...

I can't find any test code for Rowhammer though to see how it works... ;o(

...But I could guess though and probably be close enough without any said test code.