CVE-2025-58151

critical · 9.4

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.

9.4

CVSS

0.1%

EPSS (exploit prob.)

4th

EPSS percentile

2026-07-09

Published

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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Weaknesses

CWE-367

References

https://xenbits.xen.org/xsa/advisory-478.html
http://www.openwall.com/lists/oss-security/2026/01/27/2
http://xenbits.xen.org/xsa/advisory-478.html

Query this programmatically:

curl https://evil-db.io/api/v1/cve/CVE-2025-58151