Vulnerability-Lookup

GHSA-4FVG-C4GX-GXG2

Vulnerability from github – Published: 2026-08-15 06:32 – Updated: 2026-08-17 06:33

Details

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

virtio: rtc: tear down old virtqueues before restore

virtio_device_restore() resets the device and restores the negotiated features before calling ->restore(). viortc_freeze() intentionally leaves the existing virtqueues in place so the alarm queue can still wake the system, but viortc_restore() immediately calls viortc_init_vqs() without first deleting those old queues.

If virtqueue reinitialization fails on virtio-pci, the transport error path can run vp_del_vqs() against a newly allocated vp_dev->vqs array while vdev->vqs still contains the old virtqueues. vp_del_vqs() then looks up queue state through the new array and can dereference a NULL info pointer in vp_del_vq(), crashing the guest kernel during restore.

This can also happen during a non-faulty reinitialization, when one of the vp_find_vqs_msix() attempts is unsuccessful before a later attempt would succeed.

Delete the stale virtqueues before rebuilding them. If restore fails before virtio_device_ready(), reuse the remove path to stop the device. Once the device is ready, return errors directly instead of deleting the virtqueues again.

Severity

7.8 (High)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-74311"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-15T06:22:31Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nvirtio: rtc: tear down old virtqueues before restore\n\nvirtio_device_restore() resets the device and restores the negotiated\nfeatures before calling -\u003erestore(). viortc_freeze() intentionally\nleaves the existing virtqueues in place so the alarm queue can still\nwake the system, but viortc_restore() immediately calls\nviortc_init_vqs() without first deleting those old queues.\n\nIf virtqueue reinitialization fails on virtio-pci, the transport error\npath can run vp_del_vqs() against a newly allocated vp_dev-\u003evqs array\nwhile vdev-\u003evqs still contains the old virtqueues. vp_del_vqs() then\nlooks up queue state through the new array and can dereference a NULL\ninfo pointer in vp_del_vq(), crashing the guest kernel during restore.\n\nThis can also happen during a non-faulty reinitialization, when one of\nthe vp_find_vqs_msix() attempts is unsuccessful before a later attempt\nwould succeed.\n\nDelete the stale virtqueues before rebuilding them. If restore fails\nbefore virtio_device_ready(), reuse the remove path to stop the device.\nOnce the device is ready, return errors directly instead of deleting the\nvirtqueues again.",
  "id": "GHSA-4fvg-c4gx-gxg2",
  "modified": "2026-08-17T06:33:37Z",
  "published": "2026-08-15T06:32:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-74311"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/548d2208455f14e6121404c6e30e997bfe0cd264"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/79366023aa891ca31376021a7bccff6384ca1ff1"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/aebebd1e9d70b650fc9e877082e0134edcf511da"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-74311 (GCVE-0-2026-74311)

Vulnerability from cvelistv5 – Published: 2026-08-15 05:58 – Updated: 2026-08-17 05:45

Title

virtio: rtc: tear down old virtqueues before restore

Summary

In the Linux kernel, the following vulnerability has been resolved: virtio: rtc: tear down old virtqueues before restore virtio_device_restore() resets the device and restores the negotiated features before calling ->restore(). viortc_freeze() intentionally leaves the existing virtqueues in place so the alarm queue can still wake the system, but viortc_restore() immediately calls viortc_init_vqs() without first deleting those old queues. If virtqueue reinitialization fails on virtio-pci, the transport error path can run vp_del_vqs() against a newly allocated vp_dev->vqs array while vdev->vqs still contains the old virtqueues. vp_del_vqs() then looks up queue state through the new array and can dereference a NULL info pointer in vp_del_vq(), crashing the guest kernel during restore. This can also happen during a non-faulty reinitialization, when one of the vp_find_vqs_msix() attempts is unsuccessful before a later attempt would succeed. Delete the stale virtqueues before rebuilding them. If restore fails before virtio_device_ready(), reuse the remove path to stop the device. Once the device is ready, return errors directly instead of deleting the virtqueues again.

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Assigner

Linux mitre root

References

3 references

URL	Tags
https://git.kernel.org/stable/c/79366023aa891ca31…
https://git.kernel.org/stable/c/aebebd1e9d70b650f…
https://git.kernel.org/stable/c/548d2208455f14e61…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 0623c759276885c3ae88197ba6fb5c9c6ba8612f , < 79366023aa891ca31376021a7bccff6384ca1ff1 (git) Affected: 0623c759276885c3ae88197ba6fb5c9c6ba8612f , < aebebd1e9d70b650fc9e877082e0134edcf511da (git) Affected: 0623c759276885c3ae88197ba6fb5c9c6ba8612f , < 548d2208455f14e6121404c6e30e997bfe0cd264 (git)
Linux	Linux	Affected: 6.16 Unaffected: 0 , < 6.16 (semver) Unaffected: 6.18.40 , ≤ 6.18.* (semver) Unaffected: 7.1.5 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/virtio/virtio_rtc_driver.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "79366023aa891ca31376021a7bccff6384ca1ff1",
              "status": "affected",
              "version": "0623c759276885c3ae88197ba6fb5c9c6ba8612f",
              "versionType": "git"
            },
            {
              "lessThan": "aebebd1e9d70b650fc9e877082e0134edcf511da",
              "status": "affected",
              "version": "0623c759276885c3ae88197ba6fb5c9c6ba8612f",
              "versionType": "git"
            },
            {
              "lessThan": "548d2208455f14e6121404c6e30e997bfe0cd264",
              "status": "affected",
              "version": "0623c759276885c3ae88197ba6fb5c9c6ba8612f",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/virtio/virtio_rtc_driver.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.16"
            },
            {
              "lessThan": "6.16",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.40",
                  "versionStartIncluding": "6.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.5",
                  "versionStartIncluding": "6.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "6.16",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvirtio: rtc: tear down old virtqueues before restore\n\nvirtio_device_restore() resets the device and restores the negotiated\nfeatures before calling -\u003erestore(). viortc_freeze() intentionally\nleaves the existing virtqueues in place so the alarm queue can still\nwake the system, but viortc_restore() immediately calls\nviortc_init_vqs() without first deleting those old queues.\n\nIf virtqueue reinitialization fails on virtio-pci, the transport error\npath can run vp_del_vqs() against a newly allocated vp_dev-\u003evqs array\nwhile vdev-\u003evqs still contains the old virtqueues. vp_del_vqs() then\nlooks up queue state through the new array and can dereference a NULL\ninfo pointer in vp_del_vq(), crashing the guest kernel during restore.\n\nThis can also happen during a non-faulty reinitialization, when one of\nthe vp_find_vqs_msix() attempts is unsuccessful before a later attempt\nwould succeed.\n\nDelete the stale virtqueues before rebuilding them. If restore fails\nbefore virtio_device_ready(), reuse the remove path to stop the device.\nOnce the device is ready, return errors directly instead of deleting the\nvirtqueues again."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The bug is reached only through the kernel system sleep PM path (suspend/hibernate freeze/thaw/restore) that calls virtio_pci_restore() -\u003e virtio_device_restore() -\u003e viortc_restore(); it is not reachable from network packets, remote protocols, or physical device attachment.\nAC:L - Any actor who can drive a suspend/hibernate cycle on a guest with virtio-pci virtio_rtc can trigger restore; virtio-pci routinely retries MSI-X allocation policies and the commit notes the crash occurs on a failed attempt before a later one would succeed, so success does not depend on uncontrollable timing or layout.\nPR:L - Triggering suspend/hibernate/thaw is available to unprivileged local users on typical desktop, mobile, and embedded systems via logind/power interfaces or RTC alarm wake without requiring real root in the init namespace or capabilities unavailable in user namespaces.\nUI:N - Exploitation requires only initiating or allowing system suspend/hibernate and resume; no separate victim user action such as opening a file, mounting a filesystem, or clicking a prompt is needed beyond the attacker\u0027s own power-management trigger.\nS:U - The fault corrupts or crashes the same guest kernel that owns the virtio_rtc driver during PM restore; it does not cross a VM/host, IOMMU, or sandbox security boundary to impact a different authority.\nC:H - Failed virtqueue reinit leaves stale queues on vdev-\u003evqs while vp_del_vqs() indexes a new vp_dev-\u003evqs array, causing NULL or mismatched virtio_pci_vq_info teardown that can corrupt heap metadata and disclose kernel memory beyond a simple bounded fault.\nI:H - The same mismatched vp_del_vq()/vp_del_vqs() teardown can corrupt kernel linked lists and free or misuse queue metadata, providing a plausible path to further memory corruption and control-flow hijack rather than only an immediate crash.\nA:H - The documented failure mode is a NULL pointer dereference in vp_del_vq() during restore that oopses or panics the guest kernel, and a failed restore can also leave the system unable to resume cleanly from suspend/hibernate."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:45:43.827Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/79366023aa891ca31376021a7bccff6384ca1ff1"
        },
        {
          "url": "https://git.kernel.org/stable/c/aebebd1e9d70b650fc9e877082e0134edcf511da"
        },
        {
          "url": "https://git.kernel.org/stable/c/548d2208455f14e6121404c6e30e997bfe0cd264"
        }
      ],
      "title": "virtio: rtc: tear down old virtqueues before restore",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-74311",
    "datePublished": "2026-08-15T05:58:10.711Z",
    "dateReserved": "2026-08-15T05:44:03.883Z",
    "dateUpdated": "2026-08-17T05:45:43.827Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

GHSA-4FVG-C4GX-GXG2

CVE-2026-74311 (GCVE-0-2026-74311)

Tags

Sightings

Nomenclature