Researchers Detail Privilege Escalation Bugs Reported in Oracle VirtualBox

A now-patched vulnerability affecting Oracle VM VirtualBox could
be potentially exploited by an adversary to compromise the
hypervisor and cause a denial-of-service (DoS) condition.

“Easily exploitable vulnerability allows high privileged
attacker with logon to the infrastructure where Oracle VM
VirtualBox executes to compromise Oracle VM VirtualBox,” the
advisory reads^[1]. “Successful attacks of
this vulnerability can result in unauthorized ability to cause a
hang or frequently repeatable crash (complete DoS) of Oracle VM
VirtualBox”

Tracked as CVE-2021-2442^[2]
(CVSS score: 6.0), the flaw affects all versions of the product
prior to 6.1.24. SentinelLabs^[3]
researcher Max Van Amerongen has been credited with discovering and
reporting the issue, following which fixes have been rolled out^[4] by Oracle as part of its
Critical Patch Update for July 2021.

Oracle VM VirtualBox^[5]
is an open-source and cross-platform hypervisor and desktop
virtualization software that enables users to run multiple guest
operating systems such as Windows, Linux distributions, OpenBSD,
and Oracle Solaris on a single physical machine.

“Works as both an out-of-bounds read in the host process, as
well as an integer underflow. In some instances, it can also be
used to remotely DoS other Virtualbox virtual machines,” Van
Amerongen noted^[6]
back in August.

Also discovered by Van Amerongen are two other flaws affecting
versions before 6.1.20 and resolved^[9]
by Oracle in April 2021 —

• CVE-2021-2145^[10] (CVSS score: 7.5):
  Oracle VirtualBox NAT Integer Underflow Privilege Escalation
  Vulnerability
• CVE-2021-2310^[11] (CVSS score: 7.5):
  Oracle VirtualBox NAT Heap-based Buffer Overflow Privilege
  Escalation Vulnerability (affects , patched in April

Both the aforementioned issues reside within the implementation^[12] of NAT^[13] that arise from a lack
of proper validation of user-supplied data. Successful attacks of
the two shortcomings can enable a local adversary to escalate
privileges and execute arbitrary code that results in full takeover
of a vulnerable Oracle VM VirtualBox.

Given that threat actors are known to move fast to take
advantage of the security gap afforded by unpatched
vulnerabilities, it’s essential that organizations update their
VirtualBox installations to the latest version to mitigate any risk
of potential exploitation.