Description
An issue was discovered in Xen through 4.10.x. One of the fixes in XSA-260 added some safety checks to help prevent Xen livelocking with debug exceptions. Unfortunately, due to an oversight, at least one of these safety checks can be triggered by a guest. A malicious PV guest can crash Xen, leading to a Denial of Service. All Xen systems which have applied the XSA-260 fix are vulnerable. Only x86 systems are vulnerable. ARM systems are not vulnerable. Only x86 PV guests can exploit the vulnerability. x86 HVM and PVH guests cannot exploit the vulnerability. An attacker needs to be able to control hardware debugging facilities to exploit the vulnerability, but such permissions are typically available to unprivileged users.
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 | 4.8.3+xsa267+shim4.10.1+xsa267-1+deb9u9 | — |
| Debian 13 | xen | 4.8.3+xsa267+shim4.10.1+xsa267-1+deb9u9 | — |
| Debian 12 | xen | 4.8.3+xsa267+shim4.10.1+xsa267-1+deb9u9 | — |
| Debian 9 | xen | 4.8.3+xsa267+shim4.10.1+xsa267-1+deb9u9 | DSA-4236-1 |
| Debian 8 | xen | 4.4.4lts4-0+deb8u1 | DLA-1577-1 |
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 | xen | 4.10.1_06-3.3.1 | SUSE-SU-2018:1981-1 |
| SLES 12 SP3 | xen | 4.9.2_08-3.35.2 | SUSE-SU-2018:2059-1 |
| SLES 12 SP2 | xen | 4.7.6_02-43.36.1 | SUSE-SU-2018:2081-2, SUSE-SU-2018:2081-1 |
| SLES 12 SP1 | xen | 4.5.5_24-22.52.3 | SUSE-SU-2018:2069-1 |
| SLES 12 | xen | 4.4.4_34-22.71.2 | SUSE-SU-2018:2056-1 |
Show 9 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 11 SP4 | xen | 4.4.4_34-61.32.1 | SUSE-SU-2018:2037-1 |
| SLES 11 SP3 | xen | 4.2.5_21-45.25.1 | SUSE-SU-2018:2528-1 |
| SLES for SAP 12 SP3 | xen | 4.9.2_08-3.35.2 | SUSE-SU-2018:2059-1 |
| SLES for SAP 12 SP2 | xen | 4.7.6_02-43.36.1 | SUSE-SU-2018:2081-1 |
| SLES for SAP 12 SP1 | xen | 4.5.5_24-22.52.3 | SUSE-SU-2018:2069-1 |
| SLES for SAP 11 SP4 | xen | 4.4.4_34-61.32.1 | SUSE-SU-2018:2037-1 |
| SUSE OpenStack Cloud 7 | xen | 4.7.6_02-43.36.1 | SUSE-SU-2018:2081-1 |
| SUSE Linux Enterprise Point of Sale 11 SP3 | xen | 4.2.5_21-45.25.1 | SUSE-SU-2018:2528-1 |
| SUSE Enterprise Storage 4 | xen | 4.7.6_02-43.36.1 | SUSE-SU-2018:2081-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | xen | 4.15.1_01-1.2 | openSUSE-SU-2024:11520-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | xen | 4.11.0-r0 | — |
| Alpine v3.23 | xen | 4.11.0-r0 | — |
| Alpine v3.22 | xen | 4.11.0-r0 | — |
| Alpine v3.21 | xen | 4.11.0-r0 | — |
| Alpine v3.20 | xen | 4.11.0-r0 | — |
Show 15 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | xen | 4.11.0-r0 | — |
| Alpine v3.18 | xen | 4.11.0-r0 | — |
| Alpine v3.17 | xen | 4.11.0-r0 | — |
| Alpine v3.16 | xen | 4.11.0-r0 | — |
| Alpine v3.15 | xen | 4.11.0-r0 | — |
| Alpine v3.14 | xen | 4.11.0-r0 | — |
| Alpine v3.13 | xen | 4.11.0-r0 | — |
| Alpine v3.12 | xen | 4.11.0-r0 | — |
| Alpine v3.11 | xen | 4.11.0-r0 | — |
| Alpine v3.10 | xen | 4.11.0-r0 | — |
| Alpine v3.9 | xen | 4.11.0-r0 | — |
| Alpine v3.8 | xen | 4.10.1-r3 | — |
| Alpine v3.7 | xen | 4.9.3-r0 | — |
| Alpine v3.6 | xen | 4.8.4-r0 | — |
| Alpine v3.5 | xen | 4.7.6-r0 | — |
Advisories 11
- DSA-4236-1 xen - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-1577-1 xen - security update Debian Security (DSA / DLA) · Mar 9, 2026
- SUSE-SU-2018:2081-2 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:1981-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:2081-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:2528-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:2056-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:2059-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:2037-1 Security update for xen SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:2069-1 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
References
- [oss-security] 20180627 Xen Security Advisory 265 (CVE-2018-12893) - x86: #DB exception safety check can be triggered by a guest mailing-list
- DSA-4236 vendor-advisory
- https://support.citrix.com/article/CTX235748
- GLSA-201810-06 vendor-advisory
- [debian-lts-announce] 20181112 [SECURITY] [DLA 1577-1] xen security update mailing-list
- https://bugzilla.redhat.com/show_bug.cgi?id=1590979
- http://xenbits.xen.org/xsa/advisory-265.html
- 104572 vdb-entry
- 1041202 vdb-entry