Race condition in Xen

1) Race condition

EUVDB-ID: #VU49941

Risk: Low

CVSSv4.0: 4.4 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2020-27672

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

Exploit availability: No

Description

The vulnerability allows a local authenticated user to execute arbitrary code.

An issue was discovered in Xen through 4.14.x allowing x86 guest OS users to cause a host OS denial of service, achieve data corruption, or possibly gain privileges by exploiting a race condition that leads to a use-after-free involving 2MiB and 1GiB superpages.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Xen: 4.0.0 - 4.14.1

CPE2.3

• cpe:2.3:a:xen_project:xen:4.0.0:*:*:*:*:*:*:*
• cpe:2.3:a:xen_project:xen:4.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:xen_project:xen:4.0.2:*:*:*:*:*:*:*

External links

https://lists.opensuse.org/opensuse-security-announce/2020-10/msg00075.html
https://lists.opensuse.org/opensuse-security-announce/2020-11/msg00025.html
https://www.openwall.com/lists/oss-security/2021/01/19/7
https://xenbits.xen.org/xsa/advisory-345.html
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/XIK57QJOVOPWH6RFRNMGOBCROBCKMDG2/
https://security.gentoo.org/glsa/202011-06
https://www.debian.org/security/2020/dsa-4804
https://xenbits.xen.org/xsa/advisory-345.html

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.