Description
Shadow mode tracing code uses a set of per-CPU variables to avoid
cumbersome parameter passing. Some of these variables are written to
with guest controlled data, of guest controllable size. That size can
be larger than the variable, and bounding of the writes was missing.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Xen | Xen | — | — |
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 | 4.20.2+37-g61ff35323e-1 | — |
| Debian 13 | xen | 4.20.2+37-g61ff35323e-0+deb13u1 | — |
| Debian 12 | xen | 4.17.7-0+deb12u1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | xen | No fix yet | — |
| Ubuntu 26.04 LTS | xen | No fix yet | — |
| Ubuntu 25.10 | xen | No fix yet | — |
| Ubuntu 24.04 LTS | xen | No fix yet | — |
| Ubuntu 22.04 LTS | xen | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | xen | No fix yet | — |
| 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 SP7 | xen | 4.20.2_04-150700.3.22.1 | SUSE-SU-2026:0589-1, SUSE-SU-2026:0329-1 |
| SLES 12 SP5 | xen | 4.12.4_64-3.137.1 | SUSE-SU-2026:0328-1 |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLE Micro 5.5 | xen | 4.17.6_04-150500.3.59.1 | SUSE-SU-2026:0304-1 |
| SLE Micro 5.4 | xen | 4.16.7_06-150400.4.78.1 | SUSE-SU-2026:0394-1 |
| SLE Micro 5.3 | xen | 4.16.7_06-150400.4.78.1 | SUSE-SU-2026:0394-1 |
| SLE Micro 5.2 | xen | 4.14.6_28-150300.3.94.1 | SUSE-SU-2026:0303-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | xen | 4.21.0_04-1.1 | openSUSE-SU-2026:10118-1 |
| openSUSE Leap 15.6 | xen | 4.18.5_10-150600.3.37.1 | SUSE-SU-2026:0306-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | xen | 4.21.0-r2 | — |
| Alpine v3.23 | xen | 4.20.2-r1 | — |
| Alpine v3.22 | xen | 4.20.2-r1 | — |
| Alpine v3.21 | xen | 4.19.4-r1 | — |
| Alpine v3.20 | xen | 4.18.5-r4 | — |
Advisories 9
- WID-SEC-2026-0225 Xen: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 4, 2026
- openSUSE-SU-2026:10118-1 xen-4.21.0_04-1.1 on GA media SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0589-1 Security update for xen SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0328-1 Security update for xen SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0329-1 Security update for xen SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0304-1 Security update for xen SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0303-1 Security update for xen SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0306-1 Security update for xen SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0394-1 Security update for xen SUSE / openSUSE Security Updates · Feb 7, 2026