Vulnerability identifier: #VU85928
Vulnerability risk: Medium
CVSSv3.1: 5.6 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N/E:U/RL:O/RC:C]
CVE-ID:
CWE-ID:
CWE-264
Exploitation vector: Network
Exploit availability: No
Vulnerable software:
Xen
Server applications /
Virtualization software
Vendor: Xen Project
Description
The vulnerability allows a malicious guest to bypass implemented security restrictions.
The vulnerability exists due to incorrect placement of a preprocessor directive in source code, which results in a logic error when support for HVM guests is compiled out of Xen and CONFIG_HVM is disabled at Xen's build time. When a device is removed from a domain, it is not properly quarantined and retains its access to the domain to which it was previously assigned. An attacker with control over a malicious guest can retain access to the domain after it has been removed from it.
Mitigation
Install updates from vendor's website.
Vulnerable software versions
Xen: 4.17 - 4.18.0
External links
http://xenbits.xen.org/xsa/advisory-450.html
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.