CVE-2026-79609
Fixed in a distro release EPSS <1%CVSS 8.8
XPTI (Xen Page Table Isolation) was introduced to mitigate Meltdown (CVE-2017-5754, one aspect of XSA-254). This involves copying 64-bit PV guest page table entries from guest-chosen root page tables to the Xen- chosen one which is in actual use by hardware. To read the guest root page table, the directmap is used. PV guests, however, have a directmap which may not cover all memory; in particular this is the case if any memory extends beyond the 5 TiB (CONFIG_BIGMEM=y: 3.5 TiB) address boundary.
Products: xen
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| Alpine 3.21 | xen | 4.19.6-r2 |
| Alpine 3.22 | xen | 4.20.4-r2 |
| Alpine 3.23 | xen | 4.20.4-r2 |
| Alpine 3.24 | xen | 4.21.2-r2 |
| Debian 12 | xen | no fix |
| Debian 13 | xen | 4.20.4+39-gf1e1321c87-0+deb13u1 |
| Debian 14 | xen | 4.20.4+39-gf1e1321c87-1 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | xen | 4.16.7_16-150400.4.95.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | xen | 4.16.7_16-150400.4.95.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | xen | 4.17.7_02-150500.3.82.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | xen | 4.17.7_02-150500.3.82.1 |
| SUSE Linux Enterprise Micro 5.3 | xen | 4.16.7_16-150400.4.95.1 |
| SUSE Linux Enterprise Micro 5.4 | xen | 4.16.7_16-150400.4.95.1 |
| SUSE Linux Enterprise Micro 5.5 | xen | 4.17.7_02-150500.3.82.1 |
| SUSE Linux Enterprise Server 12 SP5-LTSS | xen | 4.12.4_76-3.154.1 |
| SUSE Linux Enterprise Server 15 SP4-LTSS | xen | 4.16.7_16-150400.4.95.1 |
| SUSE Linux Enterprise Server 15 SP5-LTSS | xen | 4.17.7_02-150500.3.82.1 |
| SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 | xen | 4.12.4_76-3.154.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | xen | 4.16.7_16-150400.4.95.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | xen | 4.17.7_02-150500.3.82.1 |
| Ubuntu 16.04 LTS | xen | no fix |
| Ubuntu 18.04 LTS | xen | no fix |
| Ubuntu 20.04 LTS | xen | no fix |
| Ubuntu 22.04 LTS | xen | no fix |
| Ubuntu 24.04 LTS | xen | no fix |
| Ubuntu 26.04 LTS | xen | no fix |
| Ubuntu 26.10 | xen | no fix |
| openSUSE Tumbleweed | xen | 4.22.0_06-1.1 |