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.
Metrics
Affected Vendors & Products
References
| Link | Providers |
|---|---|
| https://xenbits.xenproject.org/xsa/advisory-446.html |
|
History
Tue, 03 Jun 2025 15:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
ssvc
|
Status: PUBLISHED
Assigner: XEN
Published: 2024-01-05T16:34:59.036Z
Updated: 2025-06-03T14:40:56.728Z
Reserved: 2023-10-27T07:55:35.332Z
Link: CVE-2023-46836
Updated: 2024-08-02T20:53:21.940Z
Status : Modified
Published: 2024-01-05T17:15:11.197
Modified: 2025-06-03T15:15:42.700
Link: CVE-2023-46836
No data.