github - ghsa-q3gr-2743-cwm5

GHSA-Q3GR-2743-CWM5

Vulnerability from github – Published: 2024-05-22 09:31 – Updated: 2025-09-24 15:31

Details

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

userfaultfd: fix a race between writeprotect and exit_mmap()

A race is possible when a process exits, its VMAs are removed by exit_mmap() and at the same time userfaultfd_writeprotect() is called.

The race was detected by KASAN on a development kernel, but it appears to be possible on vanilla kernels as well.

Use mmget_not_zero() to prevent the race as done in other userfaultfd operations.

Severity ?

4.7 (Medium)


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

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2021-47461"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-362"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-05-22T07:15:11Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nuserfaultfd: fix a race between writeprotect and exit_mmap()\n\nA race is possible when a process exits, its VMAs are removed by\nexit_mmap() and at the same time userfaultfd_writeprotect() is called.\n\nThe race was detected by KASAN on a development kernel, but it appears\nto be possible on vanilla kernels as well.\n\nUse mmget_not_zero() to prevent the race as done in other userfaultfd\noperations.",
  "id": "GHSA-q3gr-2743-cwm5",
  "modified": "2025-09-24T15:31:12Z",
  "published": "2024-05-22T09:31:45Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-47461"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/149958ecd0627a9f1e9c678c25c665400054cd6a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3cda4bfffd4f755645577aaa9e96a606657b4525"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/cb185d5f1ebf900f4ae3bf84cee212e6dd035aca"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2021-47461 (GCVE-0-2021-47461)

Vulnerability from cvelistv5 – Published: 2024-05-22 06:23 – Updated: 2025-05-04 07:11

Summary

In the Linux kernel, the following vulnerability has been resolved: userfaultfd: fix a race between writeprotect and exit_mmap() A race is possible when a process exits, its VMAs are removed by exit_mmap() and at the same time userfaultfd_writeprotect() is called. The race was detected by KASAN on a development kernel, but it appears to be possible on vanilla kernels as well. Use mmget_not_zero() to prevent the race as done in other userfaultfd operations.

Severity ?

No CVSS data available.

Assigner

Linux

References

URL

Tags

	https://git.kernel.org/stable/c/3cda4bfffd4f75564…
	https://git.kernel.org/stable/c/149958ecd0627a9f1…
	https://git.kernel.org/stable/c/cb185d5f1ebf900f4…

Impacted products

Vendor

Product

Version

Linux

Affected: 63b2d4174c4ad1f40b48d7138e71bcb564c1fe03 , < 3cda4bfffd4f755645577aaa9e96a606657b4525 (git)
Affected: 63b2d4174c4ad1f40b48d7138e71bcb564c1fe03 , < 149958ecd0627a9f1e9c678c25c665400054cd6a (git)
Affected: 63b2d4174c4ad1f40b48d7138e71bcb564c1fe03 , < cb185d5f1ebf900f4ae3bf84cee212e6dd035aca (git)

Linux

Affected: 5.7
Unaffected: 0 , < 5.7 (semver)
Unaffected: 5.10.76 , ≤ 5.10.* (semver)
Unaffected: 5.14.15 , ≤ 5.14.* (semver)
Unaffected: 5.15 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2021-47461",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2024-05-22T18:15:05.306200Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2024-06-04T17:15:25.867Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      },
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-04T05:39:59.468Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/3cda4bfffd4f755645577aaa9e96a606657b4525"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/149958ecd0627a9f1e9c678c25c665400054cd6a"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://git.kernel.org/stable/c/cb185d5f1ebf900f4ae3bf84cee212e6dd035aca"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/userfaultfd.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "3cda4bfffd4f755645577aaa9e96a606657b4525",
              "status": "affected",
              "version": "63b2d4174c4ad1f40b48d7138e71bcb564c1fe03",
              "versionType": "git"
            },
            {
              "lessThan": "149958ecd0627a9f1e9c678c25c665400054cd6a",
              "status": "affected",
              "version": "63b2d4174c4ad1f40b48d7138e71bcb564c1fe03",
              "versionType": "git"
            },
            {
              "lessThan": "cb185d5f1ebf900f4ae3bf84cee212e6dd035aca",
              "status": "affected",
              "version": "63b2d4174c4ad1f40b48d7138e71bcb564c1fe03",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/userfaultfd.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.7"
            },
            {
              "lessThan": "5.7",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.76",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.14.*",
              "status": "unaffected",
              "version": "5.14.15",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "5.15",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.76",
                  "versionStartIncluding": "5.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.14.15",
                  "versionStartIncluding": "5.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15",
                  "versionStartIncluding": "5.7",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nuserfaultfd: fix a race between writeprotect and exit_mmap()\n\nA race is possible when a process exits, its VMAs are removed by\nexit_mmap() and at the same time userfaultfd_writeprotect() is called.\n\nThe race was detected by KASAN on a development kernel, but it appears\nto be possible on vanilla kernels as well.\n\nUse mmget_not_zero() to prevent the race as done in other userfaultfd\noperations."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-05-04T07:11:24.932Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/3cda4bfffd4f755645577aaa9e96a606657b4525"
        },
        {
          "url": "https://git.kernel.org/stable/c/149958ecd0627a9f1e9c678c25c665400054cd6a"
        },
        {
          "url": "https://git.kernel.org/stable/c/cb185d5f1ebf900f4ae3bf84cee212e6dd035aca"
        }
      ],
      "title": "userfaultfd: fix a race between writeprotect and exit_mmap()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2021-47461",
    "datePublished": "2024-05-22T06:23:22.373Z",
    "dateReserved": "2024-05-22T06:20:56.197Z",
    "dateUpdated": "2025-05-04T07:11:24.932Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}

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

GHSA-Q3GR-2743-CWM5

CVE-2021-47461 (GCVE-0-2021-47461)

Tags

Sightings

Nomenclature