KASLR bypass in Linux kernel

1) Information disclosure

EUVDB-ID: #VU8650

Risk: Low

CVSSv3.1: 5.7 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-14954

CWE-ID: CWE-200 - Information exposure

Exploit availability: No

Description

The vulnerability allows a local user to obtain potentially sensitive information.

The vulnerability exists due to an error in waitid implementation in kernel/exit.c in the Linux kernel through 4.13.4. A local user can accesses rusage data structures in unintended cases, which allows local users to obtain sensitive information, and bypass the KASLR protection mechanism, via a crafted system call.

Mitigation

Install update from GIT repository:
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=6c85501f2fabcfc4fc6ed97654...

Vulnerable software versions

Linux kernel: 4.13 - 4.13.4

External links

http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=6c85501f2fabcfc4fc6ed97654...
http://github.com/torvalds/linux/commit/6c85501f2fabcfc4fc6ed976543d252c4eaf4be9
http://grsecurity.net/~spender/exploits/wait_for_kaslr_to_be_effective.c
http://twitter.com/_argp/status/914021130712870912
http://twitter.com/grsecurity/status/914079864478666753

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.