8.8
High
CVE-2026-79609 XPTI (Xen Page Table Isolation) was introduced to mitigate Meltdown (CVE-2017-5754, one aspect of XSA-254)
Description
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.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| xen | Versions not published |
Other CVEs of xen
The 142 CVEs of xen →
CVE-2026-102704
arbitrary read/write via grant copy
4.4
Medium
CVE-2026-102703
arbitrary read/write via grant copy
4.4
Medium
CVE-2026-102700
With its original introduction, GNTTAB_cache_flush was made available
uniformly
4.7
Medium
CVE-2026-102699
[This CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to…
7.5
High