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Root Privileges Through Linux Kernel Bug
Lars T. writes "The H has a story about a Linux kernel bug that allows root level access. 'According to a report written by Rafal Wojtczuk (PDF), a conceptual problem in the memory management area of Linux allows local attackers to execute code at root level. The Linux issue is caused by potential overlaps between the memory areas of the stack and shared memory segments.' SUSE maintainer Andrea Arcangeli provided a fix for the problem in September 2004, but for unknown reasons this fix was not included in the Linux kernel. The bug is not related to the X Server bug found by Brad Spengler."
As the linked article notes: "SUSE itself has the fix and SUSE Linux Enterprise 9, 10 and 11 as well as openSUSE 11.1 through 11.3 do not exhibit this vulnerability."
I think what it is is that the Xorg server is an easy attack vector for the Linux kernel memory management issue.
The memory management issue is the thing that enables using a flaw in the X server to escalate privilege. If you fix the X server to not allow that kind of manipulation, you still have the kernel memory management issue that could be used by some other application to escalate privilege.
I think that fixing the X server - one mitigation is to disable the MIT-SHM extension as discussed in the pdf - really reduces the exposure but since the real problem is in the kernel, it doesn't completely remove the threat.
At least that is how I understand it...
I don't agree that it's "nothing to see here" - something has gone wrong if it took 6 years for this to happen.
Nothing to see here? Will you say the same thing when Microsoft waits 6 years to apply a fix to WinXP? :)
Yes, these things are less likely to happen with Linux. That doesn't mean Linux kernel processes are above reproach, and can't be made more responsive & accountable in cases like this where somebody obviously dropped the ball on merging a patch somewhere. I hope they spend a little time reviewing how this got missed, to make sure it's not a flaw in their process that could allow it to happen again.
I wonder how many bugs like this are lurking in closed source products, just waiting to be discovered and exploited?
I wonder how many bugs like this are lurking in open source projects, just waiting to be discovered and used against people that assume that the software they use is secure because they read Slashdot comments.
"I like to lick butts!" by MobileTatsu-NJG (#32700246) (Score:5, Informative)
What part of "local attackers" do you fail to understand?
Seven puppies were harmed during the making of this post.
Agreed it would be good to know where the breakdown in communication happened. Did it get ignored because the submitter didn't realise it was a security issue and report it as such? Did someone just miss an email somewhere? (and if so why wasn't there a system in place to keep track of current security bugs and make it bloody obvious which ones still needed fixing along with someone responsible for looking at that list and fixing them). Was the breakdown on the SUSE side or the upstream side?
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
Indeed, 5 years old and no exploit.
How do you know?
Give me Classic Slashdot or give me death!
Look at this graph: http://linuxinsecurity.blogspot.com/
Please do. Notice how the graphs show Windows with 10-12% of the issues unpatched?
That's the problem. Well that and the missing graph showing "time to patch"...
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