CVE-2020-29479

 

Published at: - 15-12-2020 07:15

Last modified: - 26-04-2022 06:12

Total changes: - 5

Description

An issue was discovered in Xen through 4.14.x. In the Ocaml xenstored implementation, the internal representation of the tree has special cases for the root node, because this node has no parent. Unfortunately, permissions were not checked for certain operations on the root node. Unprivileged guests can get and modify permissions, list, and delete the root node. (Deleting the whole xenstore tree is a host-wide denial of service.) Achieving xenstore write access is also possible. All systems using oxenstored are vulnerable. Building and using oxenstored is the default in the upstream Xen distribution, if the Ocaml compiler is available. Systems using C xenstored are not vulnerable.

Common Vulnerability Scoring System (CVSS)

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

 

Verification logic

 

Reference

• https://xenbits.xenproject.org/xsa/advisory-353.html
• DSA-4812-Third Party Advisory
• FEDORA-2020-64859a826b-Mailing List, Third Party Advisory
• FEDORA-2020-df772b417b-Mailing List, Third Party Advisory
• GLSA-202107-30-Third Party Advisory

 

Keywords

NVD

 

CVE-2020-29479

 

CVE

 

Common vulnerabilities & exposures

 

CVSS

 

Common vulnerability scoring system

 

Security

 

Vulnerabilities

 

Exposures