Improper Check for Unusual or Exceptional Conditions in Xen - CVE-2026-79602

Vulnerability identifier: #VU147398

CSH Severity: Low

CVSS v4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-79602

CWE-ID: CWE-754

Exploitation vector: Local access

Exploit availability: No public exploit available

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

The vulnerability exists due to improper handling of HVM emulation return codes in Xen HVM emulation when processing a guest with an assigned PCI device containing an I/O BAR. A local user can trigger a BUG() in Xen to cause a denial of service.

Only x86 systems are affected.

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

Install security update from vendor's website.

xen-libs-debuginfo-32bit - update to 4.12.4_74-3.151.1
xen-libs - addressed in versions 4.12.4_74-3.151.1, 4.16.7_14-150400.4.92.1, 4.17.6_16-150500.3.79.1, 4.20.4_04-150700.3.46.1
xen-tools-domU-debuginfo - addressed in versions 4.12.4_74-3.151.1, 4.16.7_14-150400.4.92.1, 4.17.6_16-150500.3.79.1, 4.20.4_04-150700.3.46.1
xen-libs-debuginfo - addressed in versions 4.12.4_74-3.151.1, 4.16.7_14-150400.4.92.1, 4.17.6_16-150500.3.79.1, 4.20.4_04-150700.3.46.1
xen-debugsource - addressed in versions 4.12.4_74-3.151.1, 4.16.7_14-150400.4.92.1, 4.17.6_16-150500.3.79.1, 4.20.4_04-150700.3.46.1
xen - addressed in versions 4.12.4_74-3.151.1, 4.16.7_14-150400.4.92.1, 4.17.6_16-150500.3.79.1, 4.20.4_04-150700.3.46.1
xen-tools-domU - addressed in versions 4.12.4_74-3.151.1, 4.16.7_14-150400.4.92.1, 4.17.6_16-150500.3.79.1, 4.20.4_04-150700.3.46.1
xen-doc-html - addressed in versions 4.12.4_74-3.151.1, 4.16.7_14-150400.4.92.1, 4.17.6_16-150500.3.79.1
xen-tools - addressed in versions 4.12.4_74-3.151.1, 4.16.7_14-150400.4.92.1, 4.17.6_16-150500.3.79.1, 4.20.4_04-150700.3.46.1
xen-libs-32bit - addressed in versions 4.12.4_74-3.151.1, 4.16.7_14-150400.4.92.1, 4.17.6_16-150500.3.79.1
xen-tools-debuginfo - addressed in versions 4.12.4_74-3.151.1, 4.16.7_14-150400.4.92.1, 4.17.6_16-150500.3.79.1, 4.20.4_04-150700.3.46.1
xen-devel - addressed in versions 4.12.4_74-3.151.1, 4.16.7_14-150400.4.92.1, 4.17.6_16-150500.3.79.1, 4.20.4_04-150700.3.46.1
xen-tools-xendomains-wait-disk - addressed in versions 4.16.7_14-150400.4.92.1, 4.17.6_16-150500.3.79.1, 4.20.4_04-150700.3.46.1
xen-libs-32bit-debuginfo - addressed in versions 4.16.7_14-150400.4.92.1, 4.17.6_16-150500.3.79.1
xen - update to 4.20.4-2.fc43
xen (Debian package) - update to 4.20.4+39-gf1e1321c87-0+deb13u1

• https://xenbits.xen.org/xsa/advisory-510.html

• Multiple vulnerabilities in Xen
• SUSE update for xen
• SUSE update for xen
• SUSE update for xen
• SUSE update for xen
• Fedora 43 update for xen
• Debian update for xen