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Linux 2.6.30 exploit posted

Linux 2.6.30 exploit posted

Posted Jul 17, 2009 16:01 UTC (Fri) by mjw (subscriber, #16740)
Parent article: Linux 2.6.30 exploit posted

Fascinating. This relies on you getting page zero mapped. Which was indeed possible because of another bug (since fixed in 2.6.31-rc3). The wonders of personalities and capabilities. Full explanation at: http://blog.cr0.org/2009/06/bypassing-linux-null-pointer....


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Linux 2.6.30 exploit posted

Posted Jul 17, 2009 16:25 UTC (Fri) by spender (subscriber, #23067) [Link]

Don't forget (as noted in the exploit) that on
machines with SELinux, due to a ridiculously
embarrassing vulnerability where both the LSM
framework and default SELinux policies are at
fault, anyone can mmap at NULL regardless of the
mmap_min_addr setting, without needing
pulseaudio or any other suid app. Just look at the
exploit.

BTW, the fact that vendor-sec had a week to
watch a video where I say I mmap at NULL on a
machine with SELinux without using pulseaudio,
and none of them thought to write a program
consisting of one line to test it...is both incredibly
sad and hilarious.

And that SELinux vulnerability surely goes back a
long time (how far exactly I haven't bothered to
check).

-Brad

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