Vulnerability · Published Oct 13, 2026 · Assigned by XEN
CVE-2026-79610grant-table: double version change race
High 8.8
In plain English
A high-severity race condition in Xen from Xen. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 4% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
XSA-501 was about issues with v1 -> v2 and v2 -> v1 changes racing certain other grant table operations. Sadly a v2 -> v1 -> v2 change has yet another effect which wasn't accounted for: During the first change, status pages would be freed. During the second change they would be allocated again. Hence across the full pair of change the addresses of the status pages may change, rendering stale previously calculated pointers into the status array.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.21 | xen | 4.19.6-r2 | ALPINE-CVE-2026-79610 |
| Alpine:v3.22 | xen | 4.20.4-r2 | ALPINE-CVE-2026-79610 |
| Alpine:v3.23 | xen | 4.20.4-r2 | ALPINE-CVE-2026-79610 |
| Alpine:v3.24 | xen | 4.21.2-r2 | ALPINE-CVE-2026-79610 |
| Debian:12 | xen | 4.17.7+13-g2445b30a44-0+deb12u1 | DEBIAN-CVE-2026-79610 |
| Debian:13 | xen | 4.20.4+39-gf1e1321c87-0+deb13u1 | DEBIAN-CVE-2026-79610 |
| Debian:14 | xen | 4.20.4+39-gf1e1321c87-1 | DEBIAN-CVE-2026-79610 |
| Ubuntu:22.04:LTS | xen | no fix listed | UBUNTU-CVE-2026-79610 |
| Ubuntu:24.04:LTS | xen | no fix listed | UBUNTU-CVE-2026-79610 |
| Ubuntu:26.04:LTS | xen | no fix listed | UBUNTU-CVE-2026-79610 |
| Ubuntu:26.10 | xen | no fix listed | UBUNTU-CVE-2026-79610 |
Affected products (as reported)
Weakness: CWE-362 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H