Slashdot Mirror
Exploits Emerge For Linux Privilege Escalation Flaw
angry tapir writes "Linux vendors are rushing to patch a privilege escalation vulnerability in the Linux kernel that can be exploited by local attackers to gain root access on the system. The vulnerability, which is identified as CVE-2012-0056, was discovered by Jüri Aedla and is caused by a failure of the Linux kernel to properly restrict access to the '/proc//mem' file."
If someone is in a position to run a local exploit, aren't you pretty much fucked anyways?
A weak SSH user account/PHP script/whatever + local privilege escalation = instant remote root
http://blog.zx2c4.com/749
Gets into the memory specifics of the bug. I found it to be far better than the actual article.
Pardon me, but I'm going to go watch Firefly now, as it appears none of you make any sense. Bye.
"Tongue tied and twisted, just an Earth bound misfit
Since this bug was introduced in Linux 2.6.39 Debian Stable (squeeze, Linux 2.6.32) is not affected. Unstable(sid, Linux 3.1) has already been patched, though Testing (wheezy) is still vulnerable.
More information here
"Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
Wuh, I think so, Brain, but if we didn't have ears, we'd look like weasels
No sig for the moment.
so someone has to be sitting in front of the boxen to exploit the exploit, why not just init 1?
Or they could use axen to destroy the boxen. Or set some foxen on them to tear them to pieces. Or they could fill the boxen with melted waxen. Or bury them in faxen. This exploit is usable by people of both sexen, so long as they pay their taxen.
There is /proc/pid/mem, a pseudofile referring to the memory of process pid. It has 0600 permissions so you can't write to the memory of other users' processes. The bug occurs when you exec an suid executable and the kernel does not change open fds for /proc/pid/mem. This way, you can open mem, dup it to stderr, and exec su with a garbage parameter. su will duly print an error, quoting the offending parameter, writing to its process memory. With a properly selected shellcode you can get root.
You either don't know what the word all means, or you don't know what the term security through obscurity means.
Guns don't kill people; Physics kills people! - John Lithgow as Dick Solomon on Third Rock From The Sun
Really? This bug was only present in kernel releases 2.6.39 and newer. Do any Android devices use kernel's based on a Linux this current? A quick search says Android 2.3. used 2.6.35 and 3.0 used 2.6.36 so the number of devices this might possibly help you root looks miniscule.
Never underestimate the dark side of the Source
Again, you don't know what security through obscurity means. If the access to the code or other design that implements the security breaks it, then that is security through obscurity. All security relies on a secret known by one party, but unknown to others. This has absolutely nothing to do with security by obscurity.
Guns don't kill people; Physics kills people! - John Lithgow as Dick Solomon on Third Rock From The Sun
Really? This bug was only present in kernel releases 2.6.39 and newer. Do any Android devices use kernel's based on a Linux this current? A quick search says Android 2.3. used 2.6.35 and 3.0 used 2.6.36 so the number of devices this might possibly help you root looks miniscule.
I am replying with my new Asus Transformer Prime, which is running ICS(Android version 4.03), kernel is 2.6.39.4.
I'm thinking this bug is God's way of saying "You are loved. Now go forth and exploit your tablet!"
Have you vetted your x86 CPU vendor's microcode for correctness? How far down do the proverbial turtles go?
Someone has already beaten every one else to the punch.
However, you need Ice Cream Sandwich and you will need access to a disassembler. Also, you cannot use this exploit for "one-click" root access as the only program that is in the Android stack that runs setuid root, is run-as. That command is statically linked so you will still need adb access so that you can disassemble the program to find it's exit call.
So there is still a fair amount of work left to be done to make this an exploit that can be used in the "wild" for Android devices. However, as a fair note. A little crowd sourcing to compile a list of offsets for different devices could greatly speed up the process. I'm actually curious if Google will patch this in there kernel.
is the very wrong quotation!
The original source quotes instead:
which is the memory as seen by a certain process whose PID is <pid>.
Moreover, there's no "/proc/mem" file and the "//" whould be interpreted as "/".
But maybe that'd be just the Slashdot editor.
Sent as ripples into the electromagnetic field. No single photon has been harmed in the process.
You seem to be in a situation where PEBKAC - it's corrupting the text of your post. Of course what you meant to say is that the Open Source model does not guarantee security but simply allows interested parties to audit for and fix security problems independent of any single company or other rights holding restricting access to the source. Generally we find that the Open Source model has worked well for Linux and has been effective at addressing security concerns. The question is sometimes not whether problems exist, but whether or not they are found and corrected.
Speaking of security on Windows - if that post of yours isn't a case where PEBKAC, you might want to install some anti virus software - looks like someone might have pwnd your machine.