Description
An issue was discovered in Xen through 4.14.x. x86 PV guest kernels can experience denial of service via SYSENTER. The SYSENTER instruction leaves various state sanitization activities to software. One of Xen's sanitization paths injects a #GP fault, and incorrectly delivers it twice to the guest. This causes the guest kernel to observe a kernel-privilege #GP fault (typically fatal) rather than a user-privilege #GP fault (usually converted into SIGSEGV/etc.). Malicious or buggy userspace can crash the guest kernel, resulting in a VM Denial of Service. All versions of Xen from 3.2 onwards are vulnerable. Only x86 systems are vulnerable. ARM platforms are not vulnerable. Only x86 systems that support the SYSENTER instruction in 64bit mode are vulnerable. This is believed to be Intel, Centaur, and Shanghai CPUs. AMD and Hygon CPUs are not believed to be vulnerable. Only x86 PV guests can exploit the vulnerability. x86 PVH / HVM guests cannot exploit the vulnerability.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | xen | 4.14.0+80-gd101b417b7-1 | — |
| Debian 13 | xen | 4.14.0+80-gd101b417b7-1 | — |
| Debian 12 | xen | 4.14.0+80-gd101b417b7-1 | — |
| Debian 10 | xen | 4.11.4+37-g3263f257ca-1 | DSA-4769-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | xen | 4.11.3+24-g14b62ab3e5-1ubuntu2.3 | USN-5617-1 |
| Ubuntu 18.04 LTS | xen | No fix yet | — |
| Ubuntu 16.04 LTS | xen | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP2 | xen | 4.13.1_08-3.10.1 | SUSE-SU-2020:2791-1 |
| SLES 15 SP1 | xen | 4.12.3_08-3.28.1 | SUSE-SU-2020:2790-1 |
| SLES 12 SP5 | xen | 4.12.3_08-3.24.1 | SUSE-SU-2020:2788-1 |
| SLES 12 SP4 | xen | 4.11.4_08-2.36.1 | SUSE-SU-2020:2786-1 |
| SLES 12 SP3 | xen | 4.9.4_12-3.74.1 | SUSE-SU-2020:2787-1 |
Show 15 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP2 | xen | 4.7.6_10-43.67.1 | SUSE-SU-2020:2822-1 |
| SLES 11 SP4 | xen | 4.4.4_44-61.55.1 | SUSE-SU-2020:14521-1 |
| SLES for SAP 15 | xen | 4.10.4_16-3.41.1 | SUSE-SU-2020:2789-1 |
| SLES for SAP 12 SP5 | xen | 4.12.3_08-3.24.1 | SUSE-SU-2020:2788-1 |
| SLES for SAP 12 SP4 | xen | 4.11.4_08-2.36.1 | SUSE-SU-2020:2786-1 |
| SLES for SAP 12 SP3 | xen | 4.9.4_12-3.74.1 | SUSE-SU-2020:2787-1 |
| SLES for SAP 12 SP2 | xen | 4.7.6_10-43.67.1 | SUSE-SU-2020:2822-1 |
| SLE HPC 15 | xen | 4.10.4_16-3.41.1 | SUSE-SU-2020:2789-1 |
| SUSE OpenStack Cloud Crowbar 9 | xen | 4.11.4_08-2.36.1 | SUSE-SU-2020:2786-1 |
| SUSE OpenStack Cloud Crowbar 8 | xen | 4.9.4_12-3.74.1 | SUSE-SU-2020:2787-1 |
| SUSE OpenStack Cloud 9 | xen | 4.11.4_08-2.36.1 | SUSE-SU-2020:2786-1 |
| SUSE OpenStack Cloud 8 | xen | 4.9.4_12-3.74.1 | SUSE-SU-2020:2787-1 |
| SUSE OpenStack Cloud 7 | xen | 4.7.6_10-43.67.1 | SUSE-SU-2020:2822-1 |
| SUSE HPE Helion OpenStack 8 | xen | 4.9.4_12-3.74.1 | SUSE-SU-2020:2787-1 |
| SUSE Enterprise Storage 5 | xen | 4.9.4_12-3.74.1 | SUSE-SU-2020:2787-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | xen | 4.15.1_01-1.2 | openSUSE-SU-2024:11520-1 |
| openSUSE Leap 15.2 | xen | 4.13.1_08-lp152.2.9.1 | openSUSE-SU-2020:1608-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | xen | 4.14.0-r1 | — |
| Alpine v3.23 | xen | 4.14.0-r1 | — |
| Alpine v3.22 | xen | 4.14.0-r1 | — |
| Alpine v3.21 | xen | 4.14.0-r1 | — |
| Alpine v3.20 | xen | 4.14.0-r1 | — |
Show 11 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | xen | 4.14.0-r1 | — |
| Alpine v3.18 | xen | 4.14.0-r1 | — |
| Alpine v3.17 | xen | 4.14.0-r1 | — |
| Alpine v3.16 | xen | 4.14.0-r1 | — |
| Alpine v3.15 | xen | 4.14.0-r1 | — |
| Alpine v3.14 | xen | 4.14.0-r1 | — |
| Alpine v3.13 | xen | 4.14.0-r1 | — |
| Alpine v3.12 | xen | 4.13.1-r4 | — |
| Alpine v3.11 | xen | 4.13.1-r4 | — |
| Alpine v3.10 | xen | 4.12.3-r4 | — |
| Alpine v3.9 | xen | 4.11.4-r2 | — |
Advisories 12
- USN-5617-1 xen vulnerabilities Ubuntu Security Notices (USN) · Apr 27, 2026
- DSA-4769-1 xen - security update Debian Security (DSA / DLA) · Mar 9, 2026
- SUSE-SU-2020:2791-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:2787-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:2786-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:14521-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:1608-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:2789-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:2822-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:2788-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:11520-1 xen-4.15.1_01-1.2 on GA media SUSE / openSUSE Security Updates · May 7, 2025
- SUSE-SU-2020:2790-1 Security update for xen SUSE / openSUSE Security Updates · May 2, 2025
References
- https://xenbits.xen.org/xsa/advisory-339.html
- FEDORA-2020-306b84fd07 vendor-advisory
- FEDORA-2020-f668e579be vendor-advisory
- DSA-4769 vendor-advisory
- openSUSE-SU-2020:1608 vendor-advisory
- FEDORA-2020-d46fe34349 vendor-advisory
- GLSA-202011-06 vendor-advisory