CVE-2020-29481

Description

An issue was discovered in Xen through 4.14.x. Access rights of Xenstore nodes are per domid. Unfortunately, existing granted access rights are not removed when a domain is being destroyed. This means that a new domain created with the same domid will inherit the access rights to Xenstore nodes from the previous domain(s) with the same domid. Because all Xenstore entries of a guest below /local/domain/<domid> are being deleted by Xen tools when a guest is destroyed, only Xenstore entries of other guests still running are affected. For example, a newly created guest domain might be able to read sensitive information that had belonged to a previously existing guest domain. Both Xenstore implementations (C and Ocaml) are vulnerable.

How to fix CVE-2020-29481

To remediate CVE-2020-29481, upgrade the affected package to a fixed version below.

• —upgrade to 4.13.2-r3 or later
• —upgrade to 4.14.0+88-g1d1d1f5391-1 or later

Is CVE-2020-29481 being exploited?

Low — EPSS is 0.1%, meaning exploitation activity has not been observed at scale.

Affected packages (2)

• from 0, < 4.13.2-r3
• from 0, < 4.14.0+88-g1d1d1f5391-1

CVSS scores

References (2)

• ADVISORYsecurity.alpinelinux.org/vuln/CVE-2020-29481
• ADVISORYsecurity-tracker.debian.org/tracker/CVE-2020-29481