CVE-2026-68178 (GCVE-0-2026-68178)
Vulnerability from cvelistv5
Published
2026-08-10 11:59
Modified
2026-10-19 20:58
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: misc: nsm: pin the module while the device is open misc_open() installs a misc driver's file operations with fops_get(), which pins file_operations::owner before replacing the file's f_op. The NSM misc device leaves nsm_dev_fops.owner unset, so opening /dev/nsm does not take a module reference on the nsm driver. If the driver is built as a module, an open file descriptor can therefore survive rmmod of the module that provides its ioctl callbacks. A later ioctl through that descriptor can call into unloaded module text. Set nsm_dev_fops.owner to THIS_MODULE so the misc core holds the module while any /dev/nsm file descriptor is open, matching the lifetime expectation for the installed file operations.
References
Impacted products
Vendor Product Version
Linux Linux Version: b9873755a6c8ccfce79094c4dce9efa3ecb1a749
Version: b9873755a6c8ccfce79094c4dce9efa3ecb1a749
Version: b9873755a6c8ccfce79094c4dce9efa3ecb1a749
Version: b9873755a6c8ccfce79094c4dce9efa3ecb1a749
 Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-68178",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-10-16T15:45:28.962889Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-416",
                "description": "CWE-416 Use After Free",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-10-19T20:58:55.830Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/misc/nsm.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "1996639f824ce9468395cdb7bcb8f467fa787e77",
              "status": "affected",
              "version": "b9873755a6c8ccfce79094c4dce9efa3ecb1a749",
              "versionType": "git"
            },
            {
              "lessThan": "1da310b94504d42001e9c32c43c5dc105b777e5f",
              "status": "affected",
              "version": "b9873755a6c8ccfce79094c4dce9efa3ecb1a749",
              "versionType": "git"
            },
            {
              "lessThan": "9e9a82d00c3d10129fc310a7547b24a679d5d920",
              "status": "affected",
              "version": "b9873755a6c8ccfce79094c4dce9efa3ecb1a749",
              "versionType": "git"
            },
            {
              "lessThan": "3b231f1e9990f4c21220d0a69733ce2105891ff9",
              "status": "affected",
              "version": "b9873755a6c8ccfce79094c4dce9efa3ecb1a749",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/misc/nsm.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.8"
            },
            {
              "lessThan": "6.8",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.101",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.42",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.6",
              "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": "6.12.101",
                  "versionStartIncluding": "6.8",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.42",
                  "versionStartIncluding": "6.8",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.6",
                  "versionStartIncluding": "6.8",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "6.8",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmisc: nsm: pin the module while the device is open\n\nmisc_open() installs a misc driver\u0027s file operations with fops_get(),\nwhich pins file_operations::owner before replacing the file\u0027s f_op.  The\nNSM misc device leaves nsm_dev_fops.owner unset, so opening /dev/nsm does\nnot take a module reference on the nsm driver.\n\nIf the driver is built as a module, an open file descriptor can therefore\nsurvive rmmod of the module that provides its ioctl callbacks.  A later\nioctl through that descriptor can call into unloaded module text.\n\nSet nsm_dev_fops.owner to THIS_MODULE so the misc core holds the module\nwhile any /dev/nsm file descriptor is open, matching the lifetime\nexpectation for the installed file operations."
        }
      ],
      "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 via local open()/ioctl syscalls on /dev/nsm (misc_open through vfs_ioctl to nsm_dev_ioctl); the Nitro Secure Module virtio driver has no network, adjacent-wireless, or physical attack surface.\nAC:L - When CONFIG_NSM=m the attacker controls the full sequence: open /dev/nsm to install fops, delete_module(\"nsm\") while fops_get(NULL) leaves the module unpinned, then ioctl on the stale fd to call unloaded text without races or external timing.\nPR:L - /dev/nsm is registered mode 0666 with no capable() checks in nsm_dev_ioctl, so any local process can open and ioctl; unloading the module needs CAP_SYS_MODULE, treated as low-privilege local capability per similar module-lifetime UAF scoring on permissive/user-namespace kernels.\nUI:N - The attacker performs open, module removal, and stale-fd ioctl from their own process; no separate victim must mount a filesystem, click a link, or take any action beyond the attacker\u0027s own operations.\nS:U - The use-after-free corrupts guest kernel memory and executes in kernel context within the Nitro Enclave; impact does not cross hypervisor, parent-instance, VM, or IOMMU security boundaries.\nC:H - Stale ioctl calls into freed module text and file_to_nsm() dereferences freed devm nsm state, exposing reclaimed kernel/module memory and adjacent virtio message buffers through the UAF window.\nI:H - Dispatching nsm_dev_ioctl through freed vmalloc module text is a kernel use-after-free that can be shaped with heap spraying to hijack control flow and achieve arbitrary kernel code execution.\nA:H - Executing code from an unloaded module or dereferencing freed nsm/virtqueue state on ioctl reliably causes kernel oops or panic, and the attacker can repeat the stale-fd ioctl to deny service."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:00:19.564Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/1996639f824ce9468395cdb7bcb8f467fa787e77"
        },
        {
          "url": "https://git.kernel.org/stable/c/1da310b94504d42001e9c32c43c5dc105b777e5f"
        },
        {
          "url": "https://git.kernel.org/stable/c/9e9a82d00c3d10129fc310a7547b24a679d5d920"
        },
        {
          "url": "https://git.kernel.org/stable/c/3b231f1e9990f4c21220d0a69733ce2105891ff9"
        }
      ],
      "title": "misc: nsm: pin the module while the device is open",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-68178",
    "datePublished": "2026-08-10T11:59:49.344Z",
    "dateReserved": "2026-07-30T09:28:09.373Z",
    "dateUpdated": "2026-10-19T20:58:55.830Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-68178\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-10-16T15:45:28.962889Z\"}}}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-416\", \"description\": \"CWE-416 Use After Free\"}]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-10-16T15:45:29.859Z\"}}], \"cna\": {\"title\": \"misc: nsm: pin the module while the device is open\", \"metrics\": [{\"cvssV3_1\": {\"version\": \"3.1\", \"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\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"AV:L - The bug is reached only via local open()/ioctl syscalls on /dev/nsm (misc_open through vfs_ioctl to nsm_dev_ioctl); the Nitro Secure Module virtio driver has no network, adjacent-wireless, or physical attack surface.\\nAC:L - When CONFIG_NSM=m the attacker controls the full sequence: open /dev/nsm to install fops, delete_module(\\\"nsm\\\") while fops_get(NULL) leaves the module unpinned, then ioctl on the stale fd to call unloaded text without races or external timing.\\nPR:L - /dev/nsm is registered mode 0666 with no capable() checks in nsm_dev_ioctl, so any local process can open and ioctl; unloading the module needs CAP_SYS_MODULE, treated as low-privilege local capability per similar module-lifetime UAF scoring on permissive/user-namespace kernels.\\nUI:N - The attacker performs open, module removal, and stale-fd ioctl from their own process; no separate victim must mount a filesystem, click a link, or take any action beyond the attacker\u0027s own operations.\\nS:U - The use-after-free corrupts guest kernel memory and executes in kernel context within the Nitro Enclave; impact does not cross hypervisor, parent-instance, VM, or IOMMU security boundaries.\\nC:H - Stale ioctl calls into freed module text and file_to_nsm() dereferences freed devm nsm state, exposing reclaimed kernel/module memory and adjacent virtio message buffers through the UAF window.\\nI:H - Dispatching nsm_dev_ioctl through freed vmalloc module text is a kernel use-after-free that can be shaped with heap spraying to hijack control flow and achieve arbitrary kernel code execution.\\nA:H - Executing code from an unloaded module or dereferencing freed nsm/virtqueue state on ioctl reliably causes kernel oops or panic, and the attacker can repeat the stale-fd ioctl to deny service.\"}]}], \"affected\": [{\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"b9873755a6c8ccfce79094c4dce9efa3ecb1a749\", \"lessThan\": \"1996639f824ce9468395cdb7bcb8f467fa787e77\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"b9873755a6c8ccfce79094c4dce9efa3ecb1a749\", \"lessThan\": \"1da310b94504d42001e9c32c43c5dc105b777e5f\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"b9873755a6c8ccfce79094c4dce9efa3ecb1a749\", \"lessThan\": \"9e9a82d00c3d10129fc310a7547b24a679d5d920\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"b9873755a6c8ccfce79094c4dce9efa3ecb1a749\", \"lessThan\": \"3b231f1e9990f4c21220d0a69733ce2105891ff9\", \"versionType\": \"git\"}], \"programFiles\": [\"drivers/misc/nsm.c\"], \"defaultStatus\": \"unaffected\"}, {\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"6.8\"}, {\"status\": \"unaffected\", \"version\": \"0\", \"lessThan\": \"6.8\", \"versionType\": \"semver\"}, {\"status\": \"unaffected\", \"version\": \"6.12.101\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.12.*\"}, {\"status\": \"unaffected\", \"version\": \"6.18.42\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.18.*\"}, {\"status\": \"unaffected\", \"version\": \"7.1.6\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"7.1.*\"}, {\"status\": \"unaffected\", \"version\": \"7.2\", \"versionType\": \"original_commit_for_fix\", \"lessThanOrEqual\": \"*\"}], \"programFiles\": [\"drivers/misc/nsm.c\"], \"defaultStatus\": \"affected\"}], \"references\": [{\"url\": \"https://git.kernel.org/stable/c/1996639f824ce9468395cdb7bcb8f467fa787e77\"}, {\"url\": \"https://git.kernel.org/stable/c/1da310b94504d42001e9c32c43c5dc105b777e5f\"}, {\"url\": \"https://git.kernel.org/stable/c/9e9a82d00c3d10129fc310a7547b24a679d5d920\"}, {\"url\": \"https://git.kernel.org/stable/c/3b231f1e9990f4c21220d0a69733ce2105891ff9\"}], \"x_generator\": {\"engine\": \"bippy-1.2.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"In the Linux kernel, the following vulnerability has been resolved:\\n\\nmisc: nsm: pin the module while the device is open\\n\\nmisc_open() installs a misc driver\u0027s file operations with fops_get(),\\nwhich pins file_operations::owner before replacing the file\u0027s f_op.  The\\nNSM misc device leaves nsm_dev_fops.owner unset, so opening /dev/nsm does\\nnot take a module reference on the nsm driver.\\n\\nIf the driver is built as a module, an open file descriptor can therefore\\nsurvive rmmod of the module that provides its ioctl callbacks.  A later\\nioctl through that descriptor can call into unloaded module text.\\n\\nSet nsm_dev_fops.owner to THIS_MODULE so the misc core holds the module\\nwhile any /dev/nsm file descriptor is open, matching the lifetime\\nexpectation for the installed file operations.\"}], \"cpeApplicability\": [{\"nodes\": [{\"negate\": false, \"cpeMatch\": [{\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.12.101\", \"versionStartIncluding\": \"6.8\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.18.42\", \"versionStartIncluding\": \"6.8\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"7.1.6\", \"versionStartIncluding\": \"6.8\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"7.2\", \"versionStartIncluding\": \"6.8\"}], \"operator\": \"OR\"}]}], \"providerMetadata\": {\"orgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"shortName\": \"Linux\", \"dateUpdated\": \"2026-08-17T05:00:19.564Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-68178\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-10-19T20:58:55.830Z\", \"dateReserved\": \"2026-07-30T09:28:09.373Z\", \"assignerOrgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"datePublished\": \"2026-08-10T11:59:49.344Z\", \"assignerShortName\": \"Linux\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.