Linux ksmbd Remote Memory Corruption via ACL Inheritance

{
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  "dataVersion": "5.2",
  "cveMetadata": {
    "cveId": "CVE-2026-8449",
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "dateUpdated": "2026-05-12T21:35:59.938Z",
    "dateReserved": "2026-05-12T21:15:19.856Z",
    "datePublished": "2026-05-12T21:34:59.782Z",
    "state": "PUBLISHED"
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      "providerMetadata": {
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
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        "dateUpdated": "2026-05-12T21:35:59.938Z"
      },
      "datePublic": "2026-05-12T22:00:00.000Z",
      "title": "Linux ksmbd Remote Memory Corruption via ACL Inheritance",
      "descriptions": [
        {
          "lang": "en",
          "value": "Linux ksmbd contains a remote memory corruption vulnerability in the ACL inheritance path that allows remote clients with directory creation permissions to trigger a heap out-of-bounds read and subsequent heap corruption by setting a crafted DACL with a malformed SID containing an inflated num_subauth field. Attackers can exploit this vulnerability by creating a directory, setting the malicious DACL via SMB2_SET_INFO, and creating child entries to cause kernel instability, denial of service, or potentially achieve privilege escalation to kernel code execution.",
          "supportingMedia": [
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              "value": "<p>Linux ksmbd contains a remote memory corruption vulnerability in the ACL inheritance path that allows remote clients with directory creation permissions to trigger a heap out-of-bounds read and subsequent heap corruption by setting a crafted DACL with a malformed SID containing an inflated num_subauth field. Attackers can exploit this vulnerability by creating a directory, setting the malicious DACL via SMB2_SET_INFO, and creating child entries to cause kernel instability, denial of service, or potentially achieve privilege escalation to kernel code execution.</p>"
            }
          ]
        }
      ],
      "affected": [
        {
          "vendor": "Linux",
          "product": "ksmbd",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "0",
              "status": "affected",
              "versionType": "git",
              "lessThanOrEqual": "996454b"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "lang": "en",
              "description": "CWE-125 Out-of-bounds Read",
              "cweId": "CWE-125",
              "type": "CWE"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://github.com/torvalds/linux/blob/6596a02b207886e9e00bb0161c7fd59fea53c081/fs/smb/server/smbacl.c",
          "tags": [
            "product",
            "technical-description"
          ]
        },
        {
          "url": "https://github.com/torvalds/linux/commit/996454bc0da84d5a1dedb1a7861823087e01a7ae",
          "tags": [
            "patch"
          ]
        },
        {
          "url": "https://www.vulncheck.com/advisories/linux-ksmbd-remote-memory-corruption-via-acl-inheritance",
          "tags": [
            "third-party-advisory"
          ]
        }
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            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "attackVector": "NETWORK",
            "attackComplexity": "LOW",
            "privilegesRequired": "LOW",
            "userInteraction": "NONE",
            "scope": "UNCHANGED",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "availabilityImpact": "HIGH",
            "baseScore": 8.8,
            "baseSeverity": "HIGH"
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      "credits": [
        {
          "lang": "en",
          "value": "Shota Zaizen",
          "type": "finder"
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}