CVE-2023-46836
- Source
- https://nvd.nist.gov/vuln/detail/CVE-2023-46836
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-46836.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2023-46836
- Downstream
- Related
- Published
- 2024-01-05T17:15:11Z
- Modified
- 2025-08-09T19:01:28Z
- Severity
-
- 4.7 (Medium) CVSS_V3 - CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N CVSS Calculator
- Summary
- [none]
- Details
-
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