Guest-to-host compromise via stale EPT entries
Published Mar 23, 2026 · Updated Mar 23, 2026
Use-after-free in Xen 4.17 and later allows guest OS users to compromise the host through stale Intel EPT paging entries. The Intel EPT paging code frees paging structures before its deferred cache flush completes, leaving cached entries that reference reassigned memory. Exploitation requires an x86 HVM or PVH guest using HAP on an Intel system with EPT and allows host-wide information disclosure, privilege escalation, or service interruption.
Summary
What happened
Use-after-free in Xen 4.17 and later allows guest OS users to compromise the host through stale Intel EPT paging entries. The Intel EPT paging code frees paging structures before its deferred cache flush completes, leaving cached entries that reference reassigned memory. Exploitation requires an x86 HVM or PVH guest using HAP on an Intel system with EPT and allows host-wide information disclosure, privilege escalation, or service interruption.
The record
- CVE
- CVE-2026-23554
- Published
- Mar 23, 2026
- Updated
- Mar 23, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-367, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Mar 23, 2026CVE publishedPublication date reported by the CVE source.
- Mar 23, 2026Record updatedLatest update available in the CVE record.
Exploitability
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Published CVSS scores
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Attacks
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Technologies
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