FreeBSD 11.0 on AMD64 bhyve Hypervisor Virtualization privileges management

Summaryinfo

A vulnerability has been found in FreeBSD 11.0 on AMD64 and classified as problematic. This affects an unknown part of the component bhyve Hypervisor. Performing a manipulation results in privileges management (Virtualization). The attack requires a local approach. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as problematic, was found in FreeBSD 11.0 on AMD64 (Operating System). This affects an unknown part of the component bhyve Hypervisor. The manipulation with an unknown input leads to a privileges management vulnerability (Virtualization). CWE is classifying the issue as CWE-269. The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor. This is going to have an impact on confidentiality, integrity, and availability.

The weakness was disclosed 10/25/2016 by Ilja van Sprundel with IOActive as FreeBSD-SA-16:32.bhyve as confirmed security advisory (Website). The advisory is shared at security.FreeBSD.org. The public release has been coordinated in cooperation with the project team. The exploitability is told to be easy. An attack has to be approached locally. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1068 for this issue. The advisory points out:

An unchecked array reference in the VGA device emulation code could potentially allow guests access to the heap of the bhyve process. Since the bhyve process is running as root, this may allow guests to obtain full control of the hosts they are running on.

Upgrading eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability. The security advisory contains the following remark:

No workaround is available, however systems not using bhyve for virtualization are not vulnerable. Additionally systems using bhyve but without the "fbuf" framebuffer device configured are not vulnerable.

The vulnerability is also documented in the vulnerability database at SecurityTracker (ID 1037098†). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

• Operating System

Name

• FreeBSD

Version

• 11.0

License

• open-source

Website

• Product: https://www.freebsd.org/

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If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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