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2 vulnerabilities found for varstored by Xen
CVE-2025-58151 (GCVE-0-2025-58151)
Vulnerability from nvd – Published: 2026-07-09 14:45 – Updated: 2026-07-09 15:41
VLAI
EPSS
VEX
Title
varstored: TOCTOU issues with mapped guest memory
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
- CWE-367 - Time-of-check time-of-use (TOCTOU) race condition
Assigner
References
Date Public
2026-01-27 13:00
Credits
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CVE-2025-58151 (GCVE-0-2025-58151)
Vulnerability from cvelistv5 – Published: 2026-07-09 14:45 – Updated: 2026-07-09 15:41
VLAI
EPSS
VEX
Title
varstored: TOCTOU issues with mapped guest memory
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
- CWE-367 - Time-of-check time-of-use (TOCTOU) race condition
Assigner
References
Date Public
2026-01-27 13:00
Credits
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