CVE-2025-27465 (GCVE-0-2025-27465)

Vulnerability from cvelistv5 – Published: 2025-07-16 09:08 – Updated: 2025-11-04 21:09
VLAI?
Title
x86: Incorrect stubs exception handling for flags recovery
Summary
Certain instructions need intercepting and emulating by Xen. In some cases Xen emulates the instruction by replaying it, using an executable stub. Some instructions may raise an exception, which is supposed to be handled gracefully. Certain replayed instructions have additional logic to set up and recover the changes to the arithmetic flags. For replayed instructions where the flags recovery logic is used, the metadata for exception handling was incorrect, preventing Xen from handling the the exception gracefully, treating it as fatal instead.
Severity ?
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
CWE
  • CWE-755 - Improper Handling of Exceptional Conditions
Assigner
XEN
References
Impacted products
Vendor Product Version
Xen Xen Unknown: consult Xen advisory XSA-470
Create a notification for this product.
Credits
This issue was discovered by Andrew Cooper of XenServer.
Show details on NVD website
To clipboard 

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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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