Vulnerability in Xen
CVE-2026-102704
[This CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] A common access pattern is a batch of Grant Copy operations acting on adjacent address ranges in the same source or destination page. For performance reasons, Xen caches details internally to reuse already validated data. The conditions on when to re-validate the internal data were not correct in some cases: - Frame numbers and grant references could wrongly be mixed up. This is CVE-2026-102703. - Copying by frame number (rather than grant reference) is permitted only when operating on the caller's own memory. The check to enforce this restriction was misplaced. This is CVE-2026-102704.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.4 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.001 (3.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 4th percentile — 3.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
The 30-day trend appears once there are two daily scores.
Affected products
- Xen — versions consult Xen advisory XSA-523
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-102704?
- CVE-2026-102704 is a medium-severity vulnerability in Xen, classified under Protection Mechanism Failure. CVSS score: 4.4/10. Published 2026-11-04.
- How severe is CVE-2026-102704?
- Medium severity. CVSS v3 base score is 4.4 out of 10.