x86: Incorrect stubs exception handling for flags recovery_CVE-2025-27465

4.3 / 10

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

Description

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.

Basic Information

ID CVE-2025-27465

Source XEN

Published Jul 16, 2025 at 09:08

Modified Jul 17, 2025 at 15:00

Affected Product

Vendor Xen

Product Xen

Version consult Xen advisory XSA-470

CWE Classification

CWE-755

References

xenbits.xenproject.org /xsa/advisory-470.html

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    "description": "Certain instructions need intercepting and emulating by Xen.  In some\ncases Xen emulates the instruction by replaying it, using an executable\nstub.  Some instructions may raise an exception, which is supposed to be\nhandled gracefully.  Certain replayed instructions have additional logic\nto set up and recover the changes to the arithmetic flags.\n\nFor replayed instructions where the flags recovery logic is used, the\nmetadata for exception handling was incorrect, preventing Xen from\nhandling the the exception gracefully, treating it as fatal instead.",
    "published": "2025-07-16T09:08:39.931Z",
    "modified": "2025-07-17T15:00:57.741Z",
    "type": "cve",
    "title": "x86: Incorrect stubs exception handling for flags recovery",
    "source": "XEN",
    "references": "https://xenbits.xenproject.org/xsa/advisory-470.html",
    "id": "CVE-2025-27465",
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