Project Zero Exploits 'Unexploitable' Glibc Bug
NotInHere (3654617) writes with news that Google's Project Zero has been busy at work. A month ago they reported an off-by-one error in glibc that would overwrite a word on the heap with NUL and were met with skepticism at its ability to be used in an attack. Google's 'Project Zero' devised an exploit of the out-of-bounds NUL write in glibc to gain root access using the setuid binary pkexec in order to convince skeptical glibc developers. 44 days after being reported, the bug has been fixed.
They even managed to defeat address space randomization on 32-bit platforms by tweaking ulimits. 64-bit systems should remain safe if they are using address space randomization.
Actually, I find the arrogance of calling an obvious bug "unexploitable" disturbing.
Most ARM is 32 bit...
Wow, sent an e-mail as suggested when clicking on "use classic" banner, and got a fast response that addressed my msg
Never say never.
Unexploitable? Srsly? GAC.
An acquaintance recently posted "Six Stages of Debugging" on his g+ page. (1. That can't happen, 2. That doesn't happen on my machine, 3. That shouldn't happen, 4. Why does that happen? 5. Oh, I see, and 6. How did that ever work). Doesn't an software dev who has been working for more than about three years go straight to No. 4?
The things they don't teach you in a CS degree.
No.
Off by ones are much easier to fix than to prove safe. The amounts of bugs called "unexploitable" until an exploit was provided is staggering. No mildly security aware person will avoid fixing a buffer overflow because it is unexploitable.
Shachar