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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-07-16 20:46 UTC
CWE
  • CWE-755 - Improper Handling of Exceptional Conditions
Assigner
XEN CNA under the mitre root
CNA scorecard D 56/100 over 48 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Xen Xen Unknown: consult Xen advisory XSA-470
guessed Create a notification for this product.
Date Public
2025-07-01 11:56
Credits
This issue was discovered by Andrew Cooper of XenServer.
Show details on NVD website
To clipboard 

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