{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "1593ddb37bd124c131fe635397df68e854a03108"
            },
            {
              "fixed": "4c3ed344a970aad51388ac3b0145b98318f0e21f"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "da087905e3270e2291c0afae39a28e7d183e5ec3"
            },
            {
              "fixed": "941a1e6eb35440336913afc88a82103291956d5d"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "62e7dd0a39c2d0d7ff03274c36df971f1b3d2d0d"
            },
            {
              "fixed": "be1ef9512a3f5a755895c24f31b334342f4aa15b"
            },
            {
              "fixed": "9bdb2ca31368b7671949dfb94a5d57ffccd01edd"
            },
            {
              "fixed": "5e489c6c47a2ac15edbaca153b9348e42c1eacab"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "191f2f444745087c3c51fd6042a0e25f42315ab0"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "6.12.23"
            },
            {
              "fixed": "6.12.88"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "6.13.11"
            },
            {
              "fixed": "6.14"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.12.88"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.30"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.14.0"
            },
            {
              "fixed": "7.0.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46139.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: use kzalloc to zero-initialize security descriptor buffer\n\nCommit 62e7dd0a39c2d (\"smb: common: change the data type of num_aces\nto le16\") split struct smb_acl's __le32 num_aces field into __le16\nnum_aces and __le16 reserved. The reserved field corresponds to Sbz2\nin the MS-DTYP ACL wire format, which must be zero [1].\n\nWhen building an ACL descriptor in build_sec_desc(), we are using a\nkmalloc()'ed descriptor buffer and writing the fields explicitly using\nle16() writes now. This never writes to the 2 byte reserved field,\nleaving it as uninitialized heap data.\n\nWhen the reserved field happens to contain non-zero slab garbage,\nSamba rejects the security descriptor with \"ndr_pull_security_descriptor\nfailed: Range Error\", causing chmod to fail with EINVAL.\n\nChange kmalloc() to kzalloc() to ensure the entire buffer is\nzero-initialized.\n\n\n[1] https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-dtyp/20233ed8-a6c6-4097-aafa-dd545ed24428",
  "id": "CVE-2026-46139",
  "modified": "2026-07-15T01:49:04.778045485Z",
  "published": "2026-05-28T09:35:55.234Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4c3ed344a970aad51388ac3b0145b98318f0e21f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5e489c6c47a2ac15edbaca153b9348e42c1eacab"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/941a1e6eb35440336913afc88a82103291956d5d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9bdb2ca31368b7671949dfb94a5d57ffccd01edd"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/be1ef9512a3f5a755895c24f31b334342f4aa15b"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46139.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-46139"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.8.0",
  "summary": "smb: client: use kzalloc to zero-initialize security descriptor buffer"
}