CVE-2020-29569

Name
CVE-2020-29569
Description
An issue was discovered in the Linux kernel through 5.10.1, as used with Xen through 4.14.x. The Linux kernel PV block backend expects the kernel thread handler to reset ring->xenblkd to NULL when stopped. However, the handler may not have time to run if the frontend quickly toggles between the states connect and disconnect. As a consequence, the block backend may re-use a pointer after it was freed. A misbehaving guest can trigger a dom0 crash by continuously connecting / disconnecting a block frontend. Privilege escalation and information leaks cannot be ruled out. This only affects systems with a Linux blkback.
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-350.html
Third Party Advisory https://www.debian.org/security/2021/dsa-4843
Third Party Advisory https://security.netapp.com/advisory/ntap-20210205-0001/
Mailing List https://lists.debian.org/debian-lts-announce/2021/02/msg00018.html
Mailing List https://lists.debian.org/debian-lts-announce/2021/03/msg00010.html
GENTOO https://security.gentoo.org/glsa/202107-30

Match rules

CPE URI Source package Min version Max version
cpe:2.3:o:xen:xen:*:*:*:*:*:*:*:* xen >= None <= 4.14.1

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-r2 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
xen 3.11-main 4.13.4-r2 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable