vulnerability

Debian: CVE-2023-46836: xen -- security update

Severity
4
CVSS
(AV:L/AC:M/Au:S/C:C/I:N/A:N)
Published
01/05/2024
Added
07/30/2024
Modified
01/28/2025

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.

Solution

debian-upgrade-xen
Title
NEW

Explore Exposure Command

Confidently identify and prioritize exposures from endpoint to cloud with full attack surface visibility and threat-aware risk context.