Privilege escalation in FreeBSD kernel

1) Privilege escalation

EUVDB-ID: #VU12450

Risk: Low

CVSSv3.1: 8.4 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:H/RL:O/RC:C]

CVE-ID: CVE-2018-8897

CWE-ID: CWE-703 - Improper Check or Handling of Exceptional Conditions

Exploit availability: Yes

Description

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

The vulnerability exists due to improper implementation of Intel 64 and IA-32 Architectures Software Developer's Manual (SDM) on multiple system kernels, which results in an unexpected behavior for #DB exceptions that are deferred by MOV SS or POP SS. A local user can execute arbitrary code with elevated privileges.

Mitigation

Install update from vendor's repository.

Vulnerable software versions

FreeBSD: 10.0 - 11.1

External links

http://www.freebsd.org/security/advisories/FreeBSD-SA-18:06.debugreg.asc

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?

Yes. This vulnerability is being exploited in the wild.