CVE-2025-58151 (GCVE-0-2025-58151)
Vulnerability from cvelistv5
Published
2026-07-09 14:45
Modified
2026-07-09 15:41
Severity ?
9.4 (Critical) - CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
CWE
  • CWE-367 - Time-of-check time-of-use (TOCTOU) race condition
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.
References
Impacted products
Vendor Product Version
Xen varstored Version: all
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