CVE-2020-29479

Name
CVE-2020-29479
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.
NVD Severity
high
Other trackers
Mailing lists
Exploits
Forges
GitHub (code, issues), Aports (code, issues)

References

Type URI
Patch https://xenbits.xenproject.org/xsa/advisory-353.html
Third Party Advisory https://www.debian.org/security/2020/dsa-4812
Mailing List https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/OBLV6L6Q24PPQ2CRFXDX4Q76KU776GKI/
Mailing List https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/2C6M6S3CIMEBACH6O7V4H2VDANMO6TVA/

Match rules

CPE URI Source package Min version Max version
cpe:2.3:o:xen:xen:*:*:*:*:*:*:*:* xen >= None <= 4.14.0

Vulnerable and fixed packages

Source package Branch Version Maintainer Status
xen 3.10-main 4.12.4-r0 None possibly vulnerable
xen 3.12-main 4.13.4-r0 Natanael Copa <ncopa@alpinelinux.org> fixed
xen 3.11-main 4.13.4-r0 Natanael Copa <ncopa@alpinelinux.org> fixed