CVE-2025-39793 (GCVE-0-2025-39793)

Vulnerability from cvelistv5 – Published: 2025-09-12 15:59 – Updated: 2025-09-29 05:59
VLAI?
Title
io_uring/memmap: cast nr_pages to size_t before shifting
Summary
In the Linux kernel, the following vulnerability has been resolved: io_uring/memmap: cast nr_pages to size_t before shifting If the allocated size exceeds UINT_MAX, then it's necessary to cast the mr->nr_pages value to size_t to prevent it from overflowing. In practice this isn't much of a concern as the required memory size will have been validated upfront, and accounted to the user. And > 4GB sizes will be necessary to make the lack of a cast a problem, which greatly exceeds normal user locked_vm settings that are generally in the kb to mb range. However, if root is used, then accounting isn't done, and then it's possible to hit this issue.
Severity ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 087f997870a948820ec366701d178f402c6a23a3 , < c6a2706e08b8a1b2d3740161c0977d38e596c1ee (git)
Affected: 087f997870a948820ec366701d178f402c6a23a3 , < a69a9b53c54e2d33e2a5b1ea4a9a71fd01c6cf3a (git)
Affected: 087f997870a948820ec366701d178f402c6a23a3 , < 33503c083fda048c77903460ac0429e1e2c0e341 (git)
Create a notification for this product.
    Linux Linux Affected: 6.14
Unaffected: 0 , < 6.14 (semver)
Unaffected: 6.15.11 , ≤ 6.15.* (semver)
Unaffected: 6.16.2 , ≤ 6.16.* (semver)
Unaffected: 6.17 , ≤ * (original_commit_for_fix)
Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "io_uring/memmap.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "c6a2706e08b8a1b2d3740161c0977d38e596c1ee",
              "status": "affected",
              "version": "087f997870a948820ec366701d178f402c6a23a3",
              "versionType": "git"
            },
            {
              "lessThan": "a69a9b53c54e2d33e2a5b1ea4a9a71fd01c6cf3a",
              "status": "affected",
              "version": "087f997870a948820ec366701d178f402c6a23a3",
              "versionType": "git"
            },
            {
              "lessThan": "33503c083fda048c77903460ac0429e1e2c0e341",
              "status": "affected",
              "version": "087f997870a948820ec366701d178f402c6a23a3",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "io_uring/memmap.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.14"
            },
            {
              "lessThan": "6.14",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.15.*",
              "status": "unaffected",
              "version": "6.15.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.16.*",
              "status": "unaffected",
              "version": "6.16.2",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.17",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.15.11",
                  "versionStartIncluding": "6.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.16.2",
                  "versionStartIncluding": "6.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.17",
                  "versionStartIncluding": "6.14",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/memmap: cast nr_pages to size_t before shifting\n\nIf the allocated size exceeds UINT_MAX, then it\u0027s necessary to cast\nthe mr-\u003enr_pages value to size_t to prevent it from overflowing. In\npractice this isn\u0027t much of a concern as the required memory size will\nhave been validated upfront, and accounted to the user. And \u003e 4GB sizes\nwill be necessary to make the lack of a cast a problem, which greatly\nexceeds normal user locked_vm settings that are generally in the kb to\nmb range. However, if root is used, then accounting isn\u0027t done, and\nthen it\u0027s possible to hit this issue."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-09-29T05:59:33.153Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/c6a2706e08b8a1b2d3740161c0977d38e596c1ee"
        },
        {
          "url": "https://git.kernel.org/stable/c/a69a9b53c54e2d33e2a5b1ea4a9a71fd01c6cf3a"
        },
        {
          "url": "https://git.kernel.org/stable/c/33503c083fda048c77903460ac0429e1e2c0e341"
        }
      ],
      "title": "io_uring/memmap: cast nr_pages to size_t before shifting",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-39793",
    "datePublished": "2025-09-12T15:59:30.388Z",
    "dateReserved": "2025-04-16T07:20:57.132Z",
    "dateUpdated": "2025-09-29T05:59:33.153Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1",
  "vulnerability-lookup:meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2025-39793\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2025-09-12T16:15:33.590\",\"lastModified\":\"2025-11-25T14:43:59.203\",\"vulnStatus\":\"Analyzed\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nio_uring/memmap: cast nr_pages to size_t before shifting\\n\\nIf the allocated size exceeds UINT_MAX, then it\u0027s necessary to cast\\nthe mr-\u003enr_pages value to size_t to prevent it from overflowing. In\\npractice this isn\u0027t much of a concern as the required memory size will\\nhave been validated upfront, and accounted to the user. And \u003e 4GB sizes\\nwill be necessary to make the lack of a cast a problem, which greatly\\nexceeds normal user locked_vm settings that are generally in the kb to\\nmb range. However, if root is used, then accounting isn\u0027t done, and\\nthen it\u0027s possible to hit this issue.\"}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":7.8,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":5.9}]},\"weaknesses\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"NVD-CWE-noinfo\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.14\",\"versionEndExcluding\":\"6.15.11\",\"matchCriteriaId\":\"6AB72A20-0D99-4FED-888D-A5B7CC969A64\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.16\",\"versionEndExcluding\":\"6.16.2\",\"matchCriteriaId\":\"BD7C087D-2415-4521-B624-30003352F899\"}]}]}],\"references\":[{\"url\":\"https://git.kernel.org/stable/c/33503c083fda048c77903460ac0429e1e2c0e341\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/a69a9b53c54e2d33e2a5b1ea4a9a71fd01c6cf3a\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/c6a2706e08b8a1b2d3740161c0977d38e596c1ee\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]}]}}"
  }
}


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 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.