CVEvulnerability

CVE-2023-46836

4.7 MEDIUM Published 2024-01-05 Modified 2026-06-17 Official page ↗
Status
Modified
Published
2024-01-05
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.1 ([email protected])
4.7 MEDIUM — CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
CVSS 3.1 (134c704f-9b21-4f2e-91b3-4a467353bcc0)
4.7 MEDIUM — CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N

Description

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.

Affected configurations

• xen xen

References