Description
An issue was discovered in Xen through 4.12.x allowing x86 PV guest OS users to gain host OS privileges by leveraging race conditions in pagetable promotion and demotion operations, because of an incomplete fix for CVE-2019-18421. XSA-299 addressed several critical issues in restartable PV type change operations. Despite extensive testing and auditing, some corner cases were missed. A malicious PV guest administrator may be able to escalate their privilege to that of the host. All security-supported versions of Xen are vulnerable. Only x86 systems are affected. Arm systems are not affected. Only x86 PV guests can leverage the vulnerability. x86 HVM and PVH guests cannot leverage the vulnerability. Note that these attacks require very precise timing, which may be difficult to exploit in practice.
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 | 4.11.3+24-g14b62ab3e5-1 | — |
| Debian 13 | xen | 4.11.3+24-g14b62ab3e5-1 | — |
| Debian 12 | xen | 4.11.3+24-g14b62ab3e5-1 | — |
| Debian 10 | xen | 4.11.3+24-g14b62ab3e5-1~deb10u1 | DSA-4602-1 |
| Debian 9 | xen | 4.8.5.final+shim4.10.4-1+deb9u12 | DSA-4602-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| 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 SP1 | xen | 4.12.1_06-3.9.1 | SUSE-SU-2019:3338-1 |
| SLES 15 | xen | 4.10.4_08-3.28.1 | SUSE-SU-2019:3309-1 |
| SLES 12 SP5 | xen | 4.12.1_10-3.8.1 | SUSE-SU-2019:3296-1 |
| SLES 12 SP4 | xen | 4.11.3_02-2.20.1 | SUSE-SU-2019:3310-1 |
| SLES 12 SP3 | xen | 4.9.4_06-3.59.1 | SUSE-SU-2020:1630-1, SUSE-SU-2019:3297-1 |
Show 13 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP2 | xen | 4.7.6_06-43.59.1 | SUSE-SU-2020:0334-1 |
| SLES 12 SP1 | xen | 4.5.5_28-22.64.1 | SUSE-SU-2020:0388-1 |
| SLES 11 SP4 | xen | 4.4.4_42-61.52.1 | SUSE-SU-2020:14444-1 |
| SLES for SAP 12 SP5 | xen | 4.12.1_10-3.8.1 | SUSE-SU-2019:3296-1 |
| SLES for SAP 12 SP4 | xen | 4.11.3_02-2.20.1 | SUSE-SU-2019:3310-1 |
| SLES for SAP 12 SP3 | xen | 4.9.4_06-3.59.1 | SUSE-SU-2020:1630-1, SUSE-SU-2019:3297-1 |
| SLES for SAP 12 SP2 | xen | 4.7.6_06-43.59.1 | SUSE-SU-2020:0334-1 |
| SLES for SAP 12 SP1 | xen | 4.5.5_28-22.64.1 | SUSE-SU-2020:0388-1 |
| SUSE OpenStack Cloud Crowbar 8 | xen | 4.9.4_06-3.59.1 | SUSE-SU-2020:1630-1, SUSE-SU-2019:3297-1 |
| SUSE OpenStack Cloud 8 | xen | 4.9.4_06-3.59.1 | SUSE-SU-2020:1630-1, SUSE-SU-2019:3297-1 |
| SUSE OpenStack Cloud 7 | xen | 4.7.6_06-43.59.1 | SUSE-SU-2020:0334-1 |
| SUSE HPE Helion OpenStack 8 | xen | 4.9.4_06-3.59.1 | SUSE-SU-2020:1630-1, SUSE-SU-2019:3297-1 |
| SUSE Enterprise Storage 5 | xen | 4.9.4_06-3.59.1 | SUSE-SU-2020:1630-1, SUSE-SU-2019:3297-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.1 | xen | 4.12.1_06-lp151.2.9.1 | openSUSE-SU-2020:0011-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | xen | 4.13.0-r0 | — |
| Alpine v3.23 | xen | 4.13.0-r0 | — |
| Alpine v3.22 | xen | 4.13.0-r0 | — |
| Alpine v3.21 | xen | 4.13.0-r0 | — |
| Alpine v3.20 | xen | 4.13.0-r0 | — |
Show 12 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | xen | 4.13.0-r0 | — |
| Alpine v3.18 | xen | 4.13.0-r0 | — |
| Alpine v3.17 | xen | 4.13.0-r0 | — |
| Alpine v3.16 | xen | 4.13.0-r0 | — |
| Alpine v3.15 | xen | 4.13.0-r0 | — |
| Alpine v3.14 | xen | 4.13.0-r0 | — |
| Alpine v3.13 | xen | 4.13.0-r0 | — |
| Alpine v3.12 | xen | 4.13.0-r0 | — |
| Alpine v3.11 | xen | 4.13.0-r0 | — |
| Alpine v3.10 | xen | 4.12.2-r0 | — |
| Alpine v3.9 | xen | 4.11.3-r1 | — |
| Alpine v3.8 | xen | 4.10.4-r2 | — |
Advisories 11
- DSA-4602-1 xen - security update Debian Security (DSA / DLA) · Mar 9, 2026
- SUSE-SU-2019:3338-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:0334-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:1630-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:0011-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:3309-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:14444-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:3297-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:3310-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:3296-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:0388-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
References
- https://xenbits.xen.org/xsa/advisory-310.html
- FEDORA-2019-6aad703290 vendor-advisory
- FEDORA-2019-2e12bd3a9a vendor-advisory
- openSUSE-SU-2020:0011 vendor-advisory
- DSA-4602 vendor-advisory
- 20200114 [SECURITY] [DSA 4602-1] xen security update mailing-list
- GLSA-202003-56 vendor-advisory