CVE-2023-46836

The fixes for XSA-422 (Branch Type Confusion) and XSA-434 (Speculative Return Stack Overflow) are not IRQ-safe. It was believed that the mitigations always operated in contexts with IRQs disabled. However, the original XSA-254 fix for Meltdown (XPTI) deliberately left interrupts enabled on two entry paths; one unconditionally, and one conditionally on whether XPTI was active. As BTC/SRSO and Meltdown affect different CPU vendors, the mitigations are not active together by default. Therefore, there is a race condition whereby a malicious PV guest can bypass BTC/SRSO protections and launch a BTC/SRSO attack against Xen.

CVSS v3 4.7 MEDIUM

4.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.0 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://xenbits.xenproject.org/xsa/advisory-446.html	Patch Vendor Advisory
http://xenbits.xen.org/xsa/advisory-446.html
https://xenbits.xenproject.org/xsa/advisory-446.html	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:o:xen:xen:*:*:*:*:*:*:*:*

History

04 Nov 2025, 20:17

Type	Values Removed	Values Added
References		() http://xenbits.xen.org/xsa/advisory-446.html -

Information

Published : 2024-01-05 17:15

Updated : 2025-11-04 20:17

NVD link : CVE-2023-46836

Mitre link : CVE-2023-46836

CVE.ORG link : CVE-2023-46836

JSON object : View

Products Affected

xen

xen

CWE

NVD-CWE-noinfo

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