{"cve":"CVE-2023-46836","nvd":{"published":"2024-01-05T17:15:11.197","modified":"2026-06-17T06:31:43.523","status":"Modified","description":"The fixes for XSA-422 (Branch Type Confusion) and XSA-434 (Speculative\nReturn Stack Overflow) are not IRQ-safe.  It was believed that the\nmitigations always operated in contexts with IRQs disabled.\n\nHowever, the original XSA-254 fix for Meltdown (XPTI) deliberately left\ninterrupts enabled on two entry paths; one unconditionally, and one\nconditionally on whether XPTI was active.\n\nAs BTC/SRSO and Meltdown affect different CPU vendors, the mitigations\nare not active together by default.  Therefore, there is a race\ncondition whereby a malicious PV guest can bypass BTC/SRSO protections\nand launch a BTC/SRSO attack against Xen.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N","score":4.7},"cwes":[],"references":["https://xenbits.xenproject.org/xsa/advisory-446.html","http://xenbits.xen.org/xsa/advisory-446.html","https://xenbits.xenproject.org/xsa/advisory-446.html"],"products":["xen:xen"],"source":"nvd","synced_at":"2026-10-19T21:43:38.875533635+00:00"},"epss":{"cve":"CVE-2023-46836","score":0.0025,"percentile":0.16357,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}