cbcvebase.
CVE-2023-46836
published 2024-01-05

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…

PriorityP422medium4.7CVSS 3.1
AVLACHPRLUINSUCHINAN
EPSS
0.25%
16.4th percentile
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

13 ranges
VendorProductVersion rangeFixed in
debianxen< xen 4.17.2+76-ge1f9cb16e2-1~deb12u1 (bookworm)xen 4.17.2+76-ge1f9cb16e2-1~deb12u1 (bookworm)
xenxen>= 0 < 4.15.5-r34.15.5-r3
xenxen>= 0 < 4.16.5-r44.16.5-r4
xenxen>= 0 < 4.16.5-r44.16.5-r4
xenxen>= 0 < 4.17.2-r44.17.2-r4
xenxen>= 0 < 4.17.2-r44.17.2-r4
xenxen>= 0 < 4.17.2-r44.17.2-r4
xenxen>= 0 < 4.17.2-r44.17.2-r4
xenxen>= 0 < 4.17.2-r44.17.2-r4
xenxen>= 0 < 4.17.2-r44.17.2-r4
xenxen>= 0 < 4.17.2+76-ge1f9cb16e2-1~deb12u14.17.2+76-ge1f9cb16e2-1~deb12u1
xenxen>= 0 < 4.17.2+76-ge1f9cb16e2-14.17.2+76-ge1f9cb16e2-1
xenxen>= 0 < 4.17.2+76-ge1f9cb16e2-14.17.2+76-ge1f9cb16e2-1

CVSS provenance

nvdv3.14.7MEDIUMCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
osv4.7MEDIUM
vendor_debian4.7MEDIUM
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