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.
References
Configurations

Configuration 1 (hide)

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

History

21 Nov 2024, 08:29

Type Values Removed Values Added
References () https://xenbits.xenproject.org/xsa/advisory-446.html - Patch, Vendor Advisory () https://xenbits.xenproject.org/xsa/advisory-446.html - Patch, Vendor Advisory

11 Jan 2024, 17:09

Type Values Removed Values Added
References () https://xenbits.xenproject.org/xsa/advisory-446.html - () https://xenbits.xenproject.org/xsa/advisory-446.html - Patch, Vendor Advisory
CWE NVD-CWE-noinfo
First Time Xen
Xen xen
CPE cpe:2.3:o:xen:xen:*:*:*:*:*:*:*:*
Summary
  • (es) Las correcciones para XSA-422 (Branch Type Confusion) y XSA-434 (Speculative Return Stack Overflow) no son seguras para IRQ. Se creía que las mitigaciones siempre operaban en contextos con las IRQ deshabilitadas. Sin embargo, la solución XSA-254 original para Meltdown (XPTI) deliberadamente dejó habilitadas las interrupciones en dos rutas de entrada; uno incondicionalmente y otro condicionalmente sobre si XPTI estaba activo. Como BTC/SRSO y Meltdown afectan a diferentes proveedores de CPU, las mitigaciones no están activas juntas de forma predeterminada. Por lo tanto, existe una condición de ejecución mediante la cual un invitado PV malicioso puede eludir las protecciones BTC/SRSO y lanzar un ataque BTC/SRSO contra Xen.
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 4.7

05 Jan 2024, 17:15

Type Values Removed Values Added
New CVE

Information

Published : 2024-01-05 17:15

Updated : 2024-11-21 08:29


NVD link : CVE-2023-46836

Mitre link : CVE-2023-46836

CVE.ORG link : CVE-2023-46836


JSON object : View

Products Affected

xen

  • xen