CVE-2026-29646

In OpenXiangShan NEMU prior to 55295c4, when running with RVH (Hypervisor extension) enabled, a VS-mode guest write to the supervisor interrupt-enable CSR (sie) may be handled incorrectly and can influence machine-level interrupt enable state (mie). This breaks privilege/virtualization isolation and can lead to denial of service or privilege-boundary violation in environments relying on NEMU for correct interrupt virtualization.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://docs.riscv.org/reference/isa/priv/hypervisor.html
https://docs.riscv.org/reference/isa/priv/machine.html
https://docs.riscv.org/reference/isa/priv/supervisor.html
https://docs.riscv.org/reference/isa/unpriv/zicsr.html
https://github.com/OpenXiangShan/NEMU/issues/951
https://github.com/OpenXiangShan/NEMU/pull/938
https://github.com/OpenXiangShan/NEMU/pull/938/commits/55295c46580456d8d5a9d5736e1fda924b8825ab

Configurations

No configuration.

History

No history.

Information

Published : 2026-04-20 21:16

Updated : 2026-06-17 10:29

NVD link : CVE-2026-29646

Mitre link : CVE-2026-29646

CVE.ORG link : CVE-2026-29646

JSON object : View

Products Affected

No product.

CWE

CWE-267

Privilege Defined With Unsafe Actions

{"id": "CVE-2026-29646", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-29646", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "total"}], "version": "2.0.3", "timestamp": "2026-04-21T13:53:04.119813Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 9.8, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 3.9}]}, "affected": [{"source": "cve@mitre.org", "affectedData": [{"vendor": "n/a", "product": "n/a", "versions": [{"status": "affected", "version": "n/a"}]}]}], "published": "2026-04-20T21:16:19.503", "references": [{"url": "https://docs.riscv.org/reference/isa/priv/hypervisor.html", "source": "cve@mitre.org"}, {"url": "https://docs.riscv.org/reference/isa/priv/machine.html", "source": "cve@mitre.org"}, {"url": "https://docs.riscv.org/reference/isa/priv/supervisor.html", "source": "cve@mitre.org"}, {"url": "https://docs.riscv.org/reference/isa/unpriv/zicsr.html", "source": "cve@mitre.org"}, {"url": "https://github.com/OpenXiangShan/NEMU/issues/951", "source": "cve@mitre.org"}, {"url": "https://github.com/OpenXiangShan/NEMU/pull/938", "source": "cve@mitre.org"}, {"url": "https://github.com/OpenXiangShan/NEMU/pull/938/commits/55295c46580456d8d5a9d5736e1fda924b8825ab", "source": "cve@mitre.org"}], "vulnStatus": "Deferred", "weaknesses": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "description": [{"lang": "en", "value": "CWE-267"}]}], "descriptions": [{"lang": "en", "value": "In OpenXiangShan NEMU prior to 55295c4, when running with RVH (Hypervisor extension) enabled, a VS-mode guest write to the supervisor interrupt-enable CSR (sie) may be handled incorrectly and can influence machine-level interrupt enable state (mie). This breaks privilege/virtualization isolation and can lead to denial of service or privilege-boundary violation in environments relying on NEMU for correct interrupt virtualization."}], "lastModified": "2026-06-17T10:29:50.740", "sourceIdentifier": "cve@mitre.org"}