CVE-2026-49429 (GCVE-0-2026-49429)
Vulnerability from cvelistv5
Published
2026-08-19 05:15
Modified
2026-08-20 03:55
CWE
  • CWE-122 - Heap-based Buffer Overflow
Summary
The ZFS_IOC_USERSPACE_MANY ioctl, used by zfs-userspace(8), truncated a 64-bit output buffer size to a 32-bit integer for the kernel allocation, but used the original 64-bit size as the buffer limit when writing records. A local user with the "userused" delegated ZFS permission can trigger a kernel heap overflow via the ZFS_IOC_USERSPACE_MANY ioctl, potentially escalating privileges.
Impacted products
Vendor Product Version
FreeBSD FreeBSD Version: 15.1-RELEASE
Version: 15.0-RELEASE
Version: 14.4-RELEASE
Version: 14.3-RELEASE
Create a notification for this product.
Show details on NVD website


{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "LOCAL",
              "availabilityImpact": "HIGH",
              "baseScore": 7.8,
              "baseSeverity": "HIGH",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "HIGH",
              "privilegesRequired": "LOW",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-49429",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-19T00:00:00+00:00",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-20T03:55:49.215Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unknown",
          "modules": [
            "zfs"
          ],
          "product": "FreeBSD",
          "vendor": "FreeBSD",
          "versions": [
            {
              "lessThan": "p1",
              "status": "affected",
              "version": "15.1-RELEASE",
              "versionType": "release"
            },
            {
              "lessThan": "p11",
              "status": "affected",
              "version": "15.0-RELEASE",
              "versionType": "release"
            },
            {
              "lessThan": "p7",
              "status": "affected",
              "version": "14.4-RELEASE",
              "versionType": "release"
            },
            {
              "lessThan": "p16",
              "status": "affected",
              "version": "14.3-RELEASE",
              "versionType": "release"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Yuxiang Yang, Yizhou Zhao, Ao Wang, Xuewei Feng, Qi Li, and Ke Xu from Tsinghua University using GLM-5.1 from Z.ai"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "Emmanuel Genier at Quarkslab"
        }
      ],
      "datePublic": "2026-06-30T20:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "The ZFS_IOC_USERSPACE_MANY ioctl, used by zfs-userspace(8), truncated a 64-bit output buffer size to a 32-bit integer for the kernel allocation, but used the original 64-bit size as the buffer limit when writing records.\n\nA local user with the \"userused\" delegated ZFS permission can trigger a kernel heap overflow via the ZFS_IOC_USERSPACE_MANY ioctl, potentially escalating privileges."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-122",
              "description": "CWE-122: Heap-based Buffer Overflow",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-19T05:15:21.198Z",
        "orgId": "63664ac6-956c-4cba-a5d0-f46076e16109",
        "shortName": "freebsd"
      },
      "references": [
        {
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://security.freebsd.org/advisories/FreeBSD-SA-26:40.zfs.asc"
        }
      ],
      "title": "Kernel heap overflow in ZFS_IOC_USERSPACE_MANY ioctl",
      "x_generator": {
        "engine": "cvelib 1.8.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "63664ac6-956c-4cba-a5d0-f46076e16109",
    "assignerShortName": "freebsd",
    "cveId": "CVE-2026-49429",
    "datePublished": "2026-08-19T05:15:21.198Z",
    "dateReserved": "2026-05-29T20:24:28.616Z",
    "dateUpdated": "2026-08-20T03:55:49.215Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 7.8, \"attackVector\": \"LOCAL\", \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\", \"integrityImpact\": \"HIGH\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"HIGH\", \"privilegesRequired\": \"LOW\", \"confidentialityImpact\": \"HIGH\"}}, {\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-49429\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-08-19T12:16:14.445112Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-08-19T12:16:32.478Z\"}}], \"cna\": {\"title\": \"Kernel heap overflow in ZFS_IOC_USERSPACE_MANY ioctl\", \"credits\": [{\"lang\": \"en\", \"type\": \"finder\", \"value\": \"Yuxiang Yang, Yizhou Zhao, Ao Wang, Xuewei Feng, Qi Li, and Ke Xu from Tsinghua University using GLM-5.1 from Z.ai\"}, {\"lang\": \"en\", \"type\": \"finder\", \"value\": \"Emmanuel Genier at Quarkslab\"}], \"affected\": [{\"vendor\": \"FreeBSD\", \"modules\": [\"zfs\"], \"product\": \"FreeBSD\", \"versions\": [{\"status\": \"affected\", \"version\": \"15.1-RELEASE\", \"lessThan\": \"p1\", \"versionType\": \"release\"}, {\"status\": \"affected\", \"version\": \"15.0-RELEASE\", \"lessThan\": \"p11\", \"versionType\": \"release\"}, {\"status\": \"affected\", \"version\": \"14.4-RELEASE\", \"lessThan\": \"p7\", \"versionType\": \"release\"}, {\"status\": \"affected\", \"version\": \"14.3-RELEASE\", \"lessThan\": \"p16\", \"versionType\": \"release\"}], \"defaultStatus\": \"unknown\"}], \"datePublic\": \"2026-06-30T20:00:00.000Z\", \"references\": [{\"url\": \"https://security.freebsd.org/advisories/FreeBSD-SA-26:40.zfs.asc\", \"tags\": [\"vendor-advisory\"]}], \"x_generator\": {\"engine\": \"cvelib 1.8.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"The ZFS_IOC_USERSPACE_MANY ioctl, used by zfs-userspace(8), truncated a 64-bit output buffer size to a 32-bit integer for the kernel allocation, but used the original 64-bit size as the buffer limit when writing records.\\n\\nA local user with the \\\"userused\\\" delegated ZFS permission can trigger a kernel heap overflow via the ZFS_IOC_USERSPACE_MANY ioctl, potentially escalating privileges.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-122\", \"description\": \"CWE-122: Heap-based Buffer Overflow\"}]}], \"providerMetadata\": {\"orgId\": \"63664ac6-956c-4cba-a5d0-f46076e16109\", \"shortName\": \"freebsd\", \"dateUpdated\": \"2026-08-19T05:15:21.198Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-49429\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-08-20T03:55:49.215Z\", \"dateReserved\": \"2026-05-29T20:24:28.616Z\", \"assignerOrgId\": \"63664ac6-956c-4cba-a5d0-f46076e16109\", \"datePublished\": \"2026-08-19T05:15:21.198Z\", \"assignerShortName\": \"freebsd\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

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.


Loading…

Loading…