CRITICAL
varstored: TOCTOU issues with mapped guest memory
Published Jul 9, 2026
9.4
CRITICALCVSS 4.0
EPSS 0.14%
Description
varstored is a component of the Xapi toolstack handling UEFI Variables for a VM. It has a communication path with OVMF inside the VM involving mapping a buffer prepared by OVMF.
Within varstored, there were insufficient compiler barriers, creating TOCTOU issues with data in the shared buffer.
The exact vulnerable behaviour depends on the code generated by the compiler. In a build of varstored using default settings, the attacker can control an index used in a jump table.
Affected products
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- Version allStatusaffectedConstraints-
- Version
No data.
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Weaknesses (1)
References (4)
Change history (0)
No recorded changes yet.
Sources
CVE.org / MITRE
Status PUBLISHED
Assigner XEN
Published Jul 9, 2026
Updated Jul 9, 2026
Reserved Aug 26, 2025
Link CVE-2025-58151
CISA Vulnrichment
Updated Jul 9, 2026
ENISA EUVD
EUVD-2025-210447 Assigner XEN
Published Jul 9, 2026
Updated Jul 9, 2026
Exploited since n/a
Link EUVD-2025-210447