Description
The adjustments made for XSA-379 as well as those subsequently becoming XSA-387 still left a race window, when a HVM or PVH guest does a grant table version change from v2 to v1 in parallel with mapping the status page(s) via XENMEM_add_to_physmap. Some of the status pages may then be freed while mappings of them would still be inserted into the guest's secondary (P2M) page tables.
Affected products
xen: xen
References3
- xenbits.xenproject.org/xsa/advisory-486.html MitigationPatchVendor Advisory
- xenbits.xen.org/xsa/advisory-486.html MitigationPatchVendor Advisory
- www.openwall.com/lists/oss-security/2026/04/28/13 Mailing ListMitigationPatchThird Party Advisory
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 2 · as of 14 November 2026
- CWE
- CWE-362
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