Out-of-bounds write in Xen - CVE-2026-62434

 

Out-of-bounds write in Xen - CVE-2026-62434

Published: July 29, 2026


Vulnerability identifier: #VU140014
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-62434
CWE-ID: CWE-787
Exploitation vector: Local access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to memory corruption in Xen memory management state when reclaiming special pages in populate-on-demand guests. A local user can attempt to reclaim pages that are not regular guest ram to cause a denial of service.

Only x86 HVM and PVH guests started in populate-on-demand mode are believed to be able to leverage the vulnerability.


Affected software

Xen
SUSE Linux Enterprise Server 15 SP5
SUSE Linux Enterprise Server 12 SP5
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise Server 15 SP4
SUSE Linux Enterprise Server 15 SP6
Debian Linux
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise High Performance Computing LTSS 15
SUSE Linux Enterprise High Performance Computing ESPOS 15
SUSE Linux Enterprise High Performance Computing 15
SUSE Linux Enterprise Server for SAP Applications 12
SUSE Linux Enterprise High Performance Computing 12
SUSE Linux Enterprise Server 12
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise Micro
SUSE Linux Enterprise Micro for Rancher
Basesystem Module
Server Applications Module
openSUSE Leap
Fedora
Citrix XenServer
xen-debugsource
xen-tools-domU
xen-libs
xen-devel
xen-libs-debuginfo-32bit
xen-libs-debuginfo
xen-libs-32bit
xen-tools-domU-debuginfo
xen-tools-debuginfo
xen-tools
xen-doc-html
xen
xen-libs-32bit-debuginfo
xen-tools-xendomains-wait-disk
xen (Debian package)

How to mitigate CVE-2026-62434

Install security update from vendor's website.

xen-debugsource - addressed in versions 4.12.4_72-3.148.4, 4.16.7_12-150400.4.89.3, 4.17.6_14-150500.3.76.3, 4.18.5_20-150600.3.53.3, 4.20.4_04-150700.3.46.1
xen-tools-domU - addressed in versions 4.12.4_72-3.148.4, 4.16.7_12-150400.4.89.3, 4.17.6_14-150500.3.76.3, 4.18.5_20-150600.3.53.3, 4.20.4_04-150700.3.46.1
xen-libs - addressed in versions 4.12.4_72-3.148.4, 4.16.7_12-150400.4.89.3, 4.17.6_14-150500.3.76.3, 4.18.5_20-150600.3.53.3, 4.20.4_04-150700.3.46.1
xen-devel - addressed in versions 4.12.4_72-3.148.4, 4.16.7_12-150400.4.89.3, 4.17.6_14-150500.3.76.3, 4.18.5_20-150600.3.53.3, 4.20.4_04-150700.3.46.1
xen-libs-debuginfo-32bit - update to 4.12.4_72-3.148.4
xen-libs-debuginfo - addressed in versions 4.12.4_72-3.148.4, 4.16.7_12-150400.4.89.3, 4.17.6_14-150500.3.76.3, 4.18.5_20-150600.3.53.3, 4.20.4_04-150700.3.46.1
xen-libs-32bit - addressed in versions 4.12.4_72-3.148.4, 4.16.7_12-150400.4.89.3, 4.17.6_14-150500.3.76.3, 4.18.5_20-150600.3.53.3
xen-tools-domU-debuginfo - addressed in versions 4.12.4_72-3.148.4, 4.16.7_12-150400.4.89.3, 4.17.6_14-150500.3.76.3, 4.18.5_20-150600.3.53.3, 4.20.4_04-150700.3.46.1
xen-tools-debuginfo - addressed in versions 4.12.4_72-3.148.4, 4.16.7_12-150400.4.89.3, 4.17.6_14-150500.3.76.3, 4.18.5_20-150600.3.53.3, 4.20.4_04-150700.3.46.1
xen-tools - addressed in versions 4.12.4_72-3.148.4, 4.16.7_12-150400.4.89.3, 4.17.6_14-150500.3.76.3, 4.18.5_20-150600.3.53.3, 4.20.4_04-150700.3.46.1
xen-doc-html - addressed in versions 4.12.4_72-3.148.4, 4.16.7_12-150400.4.89.3, 4.17.6_14-150500.3.76.3, 4.18.5_20-150600.3.53.3
xen - addressed in versions 4.12.4_72-3.148.4, 4.16.7_12-150400.4.89.3, 4.17.6_14-150500.3.76.3, 4.18.5_20-150600.3.53.3, 4.20.4_04-150700.3.46.1
xen-libs-32bit-debuginfo - addressed in versions 4.16.7_12-150400.4.89.3, 4.17.6_14-150500.3.76.3, 4.18.5_20-150600.3.53.3
xen-tools-xendomains-wait-disk - addressed in versions 4.16.7_12-150400.4.89.3, 4.17.6_14-150500.3.76.3, 4.18.5_20-150600.3.53.3, 4.20.4_04-150700.3.46.1
xen (Debian package) - update to 4.20.3+127-gc42374a105-0+deb13u1
xen - addressed in versions 4.20.4-1.fc43, 4.21.2-1.fc44

External References

Related Security Bulletins