FKIE_CVE-2026-29646

Vulnerability from fkie_nvd - Published: 2026-04-20 21:16 - Updated: 2026-06-17 10:29
Severity
9.8 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Summary
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.
References
cve@mitre.orghttps://docs.riscv.org/reference/isa/priv/hypervisor.html
cve@mitre.orghttps://docs.riscv.org/reference/isa/priv/machine.html
cve@mitre.orghttps://docs.riscv.org/reference/isa/priv/supervisor.html
cve@mitre.orghttps://docs.riscv.org/reference/isa/unpriv/zicsr.html
cve@mitre.orghttps://github.com/OpenXiangShan/NEMU/issues/951
cve@mitre.orghttps://github.com/OpenXiangShan/NEMU/pull/938
cve@mitre.orghttps://github.com/OpenXiangShan/NEMU/pull/938/commits/55295c46580456d8d5a9d5736e1fda924b8825ab
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "n/a",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ],
      "source": "cve@mitre.org"
    }
  ],
  "cveTags": [],
  "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."
    }
  ],
  "id": "CVE-2026-29646",
  "lastModified": "2026-06-17T10:29:50.740",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 9.8,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.9,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-29646",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-04-21T13:53:04.119813Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-04-20T21:16:19.503",
  "references": [
    {
      "source": "cve@mitre.org",
      "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"
    }
  ],
  "sourceIdentifier": "cve@mitre.org",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-267"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}



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