Privilege escalation in Linux Kernel

1) Privilege escalation

EUVDB-ID: #VU15526

Risk: Low

CVSSv3.1: 8.3 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:P/RL:U/RC:C]

CVE-ID: CVE-2018-18559

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

Exploit availability: No

Description

The vulnerability allows a local attacker to gain elevated privileges on the target system.

The vulnerability exists due to improper handling of a certain multithreaded case involving packet_do_bind unregister and packet_notifier register actions after a race condition between fanout_add, from setsockopt, and a bind on an AF_PACKET socket. A local attacker can execute a program or file that submits malicious input, trigger a use-after-free condition and execute arbitrary code with kernel privileges.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation

Cybersecurity Help is currently unaware of any solutions addressing the vulnerability.

Vulnerable software versions

Linux kernel: 4.15.0 - 4.19

CPE2.3

• cpe:2.3:o:linux_foundation:linux_kernel:4.19:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.18.16:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.17.19:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.16.18:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.15.18:*:*:*:*:*:*:*

External links

http://blogs.securiteam.com/index.php/archives/3731

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. However, proof of concept for this vulnerability is available.