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

Vulnerability from cvelistv5 – Published: 2024-05-22 06:23 – Updated: 2026-08-05 08:47
VLAI
Title
userfaultfd: fix a race between writeprotect and exit_mmap()
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
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-05-22 18:15 UTC
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6641 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 63b2d4174c4ad1f40b48d7138e71bcb564c1fe03 , < 3cda4bfffd4f755645577aaa9e96a606657b4525 (git)
Affected: 63b2d4174c4ad1f40b48d7138e71bcb564c1fe03 , < 149958ecd0627a9f1e9c678c25c665400054cd6a (git)
Affected: 63b2d4174c4ad1f40b48d7138e71bcb564c1fe03 , < cb185d5f1ebf900f4ae3bf84cee212e6dd035aca (git)
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Linux 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)
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Show details on NVD website
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              {
                "lang": "en",
                "value": "CWE-362"
              }
            ],
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      "id": "CVE-2021-47461",
      "initial_release_date": "2021-01-01T00:00:00+00:00",
      "product_status:fixed": "413",
      "product_status:known_affected": "42",
      "product_status:known_not_affected": "112",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: userfaultfd: fix a race between writeprotect and exit_mmap()",
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      "product_status:recommended": "472",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2021-47461",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/2024/cve-2021-47461.json",
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              {
                "other": {
                  "content": {
                    "id": "CVE-2021-47461",
                    "options": [
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                      },
                      {
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                      },
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                    "timestamp": "2024-05-22T18:15:05.306200Z",
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      "cveMetadata": {
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        "assignerShortName": "Linux",
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        "datePublished": "2024-05-22T06:23:22.373Z",
        "dateReserved": "2024-05-22T06:20:56.197Z",
        "dateUpdated": "2026-08-05T08:47:57.329Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



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Sightings

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Nomenclature

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