Vulnerability-Lookup

CVE-2026-31591 (GCVE-0-2026-31591)

Vulnerability from cvelistv5 – Published: 2026-04-24 14:42 – Updated: 2026-04-24 14:42

Title

KVM: SEV: Lock all vCPUs when synchronzing VMSAs for SNP launch finish

Summary

In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Lock all vCPUs when synchronzing VMSAs for SNP launch finish Lock all vCPUs when synchronizing and encrypting VMSAs for SNP guests, as allowing userspace to manipulate and/or run a vCPU while its state is being synchronized would at best corrupt vCPU state, and at worst crash the host kernel. Opportunistically assert that vcpu->mutex is held when synchronizing its VMSA (the SEV-ES path already locks vCPUs).

Severity ?

No CVSS data available.

Assigner

Linux

References

URL

Tags

	https://git.kernel.org/stable/c/30fd9d8c820877421…
	https://git.kernel.org/stable/c/4df77742e8b9a6b93…
	https://git.kernel.org/stable/c/c87938fc7d99a06a7…

Impacted products

Vendor

Product

Version

Linux

Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 30fd9d8c82087742168db779929d8be0459b0716 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 4df77742e8b9a6b935bdf46f02fd0aca4d4ee7f5 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < c87938fc7d99a06a7e5477c45b4e5a4148f85d66 (git)

Linux

Unaffected: 6.18.24 , ≤ 6.18.* (semver)
Unaffected: 6.19.14 , ≤ 6.19.* (semver)
Unaffected: 7.0.1 , ≤ 7.0.* (semver)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/x86/kvm/svm/sev.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "30fd9d8c82087742168db779929d8be0459b0716",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "4df77742e8b9a6b935bdf46f02fd0aca4d4ee7f5",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "c87938fc7d99a06a7e5477c45b4e5a4148f85d66",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "arch/x86/kvm/svm/sev.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.24",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.14",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.0.*",
              "status": "unaffected",
              "version": "7.0.1",
              "versionType": "semver"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.24",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0.1",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: SEV: Lock all vCPUs when synchronzing VMSAs for SNP launch finish\n\nLock all vCPUs when synchronizing and encrypting VMSAs for SNP guests, as\nallowing userspace to manipulate and/or run a vCPU while its state is being\nsynchronized would at best corrupt vCPU state, and at worst crash the host\nkernel.\n\nOpportunistically assert that vcpu-\u003emutex is held when synchronizing its\nVMSA (the SEV-ES path already locks vCPUs)."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-24T14:42:18.276Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/30fd9d8c82087742168db779929d8be0459b0716"
        },
        {
          "url": "https://git.kernel.org/stable/c/4df77742e8b9a6b935bdf46f02fd0aca4d4ee7f5"
        },
        {
          "url": "https://git.kernel.org/stable/c/c87938fc7d99a06a7e5477c45b4e5a4148f85d66"
        }
      ],
      "title": "KVM: SEV: Lock all vCPUs when synchronzing VMSAs for SNP launch finish",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-31591",
    "datePublished": "2026-04-24T14:42:18.276Z",
    "dateReserved": "2026-03-09T15:48:24.120Z",
    "dateUpdated": "2026-04-24T14:42:18.276Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-31591",
      "date": "2026-04-26",
      "epss": "0.00017",
      "percentile": "0.0407"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-31591\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-04-24T15:16:36.480\",\"lastModified\":\"2026-04-24T17:51:40.810\",\"vulnStatus\":\"Awaiting Analysis\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nKVM: SEV: Lock all vCPUs when synchronzing VMSAs for SNP launch finish\\n\\nLock all vCPUs when synchronizing and encrypting VMSAs for SNP guests, as\\nallowing userspace to manipulate and/or run a vCPU while its state is being\\nsynchronized would at best corrupt vCPU state, and at worst crash the host\\nkernel.\\n\\nOpportunistically assert that vcpu-\u003emutex is held when synchronizing its\\nVMSA (the SEV-ES path already locks vCPUs).\"}],\"metrics\":{},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/30fd9d8c82087742168db779929d8be0459b0716\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/4df77742e8b9a6b935bdf46f02fd0aca4d4ee7f5\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/c87938fc7d99a06a7e5477c45b4e5a4148f85d66\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}"
  }
}

FKIE_CVE-2026-31591

Vulnerability from fkie_nvd - Published: 2026-04-24 15:16 - Updated: 2026-04-24 17:51

Severity ?

Summary

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/30fd9d8c82087742168db779929d8be0459b0716
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/4df77742e8b9a6b935bdf46f02fd0aca4d4ee7f5
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/c87938fc7d99a06a7e5477c45b4e5a4148f85d66

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: SEV: Lock all vCPUs when synchronzing VMSAs for SNP launch finish\n\nLock all vCPUs when synchronizing and encrypting VMSAs for SNP guests, as\nallowing userspace to manipulate and/or run a vCPU while its state is being\nsynchronized would at best corrupt vCPU state, and at worst crash the host\nkernel.\n\nOpportunistically assert that vcpu-\u003emutex is held when synchronizing its\nVMSA (the SEV-ES path already locks vCPUs)."
    }
  ],
  "id": "CVE-2026-31591",
  "lastModified": "2026-04-24T17:51:40.810",
  "metrics": {},
  "published": "2026-04-24T15:16:36.480",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/30fd9d8c82087742168db779929d8be0459b0716"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/4df77742e8b9a6b935bdf46f02fd0aca4d4ee7f5"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/c87938fc7d99a06a7e5477c45b4e5a4148f85d66"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Awaiting Analysis"
}

MSRC_CVE-2026-31591

Vulnerability from csaf_microsoft - Published: 2026-04-02 00:00 - Updated: 2026-04-26 01:07

Summary

KVM: SEV: Lock all vCPUs when synchronzing VMSAs for SNP launch finish

Notes

Additional Resources: To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle

Disclaimer: The information provided in the Microsoft Knowledge Base is provided \"as is\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.

CVE-2026-31591

References

URL

Category

	https://msrc.microsoft.com/csaf/vex/2026/msrc_cve…	self
	https://support.microsoft.com/lifecycle	external
	https://www.first.org/cvss	external
	https://msrc.microsoft.com/csaf/vex/2026/msrc_cve…	self

JSON

To clipboard

{
  "document": {
    "category": "csaf_vex",
    "csaf_version": "2.0",
    "distribution": {
      "text": "Public",
      "tlp": {
        "label": "WHITE",
        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "en-US",
    "notes": [
      {
        "category": "general",
        "text": "To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle",
        "title": "Additional Resources"
      },
      {
        "category": "legal_disclaimer",
        "text": "The information provided in the Microsoft Knowledge Base is provided \\\"as is\\\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.",
        "title": "Disclaimer"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "secure@microsoft.com",
      "name": "Microsoft Security Response Center",
      "namespace": "https://msrc.microsoft.com"
    },
    "references": [
      {
        "category": "self",
        "summary": "CVE-2026-31591 KVM: SEV: Lock all vCPUs when synchronzing VMSAs for SNP launch finish - VEX",
        "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-31591.json"
      },
      {
        "category": "external",
        "summary": "Microsoft Support Lifecycle",
        "url": "https://support.microsoft.com/lifecycle"
      },
      {
        "category": "external",
        "summary": "Common Vulnerability Scoring System",
        "url": "https://www.first.org/cvss"
      }
    ],
    "title": "KVM: SEV: Lock all vCPUs when synchronzing VMSAs for SNP launch finish",
    "tracking": {
      "current_release_date": "2026-04-26T01:07:39.000Z",
      "generator": {
        "date": "2026-04-26T07:27:57.369Z",
        "engine": {
          "name": "MSRC Generator",
          "version": "1.0"
        }
      },
      "id": "msrc_CVE-2026-31591",
      "initial_release_date": "2026-04-02T00:00:00.000Z",
      "revision_history": [
        {
          "date": "2026-04-26T01:07:39.000Z",
          "legacy_version": "1",
          "number": "1",
          "summary": "Information published."
        }
      ],
      "status": "final",
      "version": "1"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version",
                "name": "3.0",
                "product": {
                  "name": "Azure Linux 3.0",
                  "product_id": "17084"
                }
              }
            ],
            "category": "product_name",
            "name": "Azure Linux"
          }
        ],
        "category": "vendor",
        "name": "Microsoft"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-31591",
      "notes": [
        {
          "category": "general",
          "text": "Linux",
          "title": "Assigning CNA"
        }
      ],
      "product_status": {
        "under_investigation": [
          "17084-1"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "CVE-2026-31591 KVM: SEV: Lock all vCPUs when synchronzing VMSAs for SNP launch finish - VEX",
          "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-31591.json"
        }
      ],
      "title": "KVM: SEV: Lock all vCPUs when synchronzing VMSAs for SNP launch finish"
    }
  ]
}

GHSA-FVVW-8GW5-VW5F

Vulnerability from github – Published: 2026-04-24 15:32 – Updated: 2026-04-24 15:32

Details

In the Linux kernel, the following vulnerability has been resolved:

KVM: SEV: Lock all vCPUs when synchronzing VMSAs for SNP launch finish

Lock all vCPUs when synchronizing and encrypting VMSAs for SNP guests, as allowing userspace to manipulate and/or run a vCPU while its state is being synchronized would at best corrupt vCPU state, and at worst crash the host kernel.

Opportunistically assert that vcpu->mutex is held when synchronizing its VMSA (the SEV-ES path already locks vCPUs).

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-31591"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-04-24T15:16:36Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: SEV: Lock all vCPUs when synchronzing VMSAs for SNP launch finish\n\nLock all vCPUs when synchronizing and encrypting VMSAs for SNP guests, as\nallowing userspace to manipulate and/or run a vCPU while its state is being\nsynchronized would at best corrupt vCPU state, and at worst crash the host\nkernel.\n\nOpportunistically assert that vcpu-\u003emutex is held when synchronizing its\nVMSA (the SEV-ES path already locks vCPUs).",
  "id": "GHSA-fvvw-8gw5-vw5f",
  "modified": "2026-04-24T15:32:34Z",
  "published": "2026-04-24T15:32:34Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31591"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/30fd9d8c82087742168db779929d8be0459b0716"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4df77742e8b9a6b935bdf46f02fd0aca4d4ee7f5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c87938fc7d99a06a7e5477c45b4e5a4148f85d66"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

CVE-2026-31591 (GCVE-0-2026-31591)

FKIE_CVE-2026-31591

MSRC_CVE-2026-31591

GHSA-FVVW-8GW5-VW5F

Tags

Sightings

Nomenclature