CVE-2026-110714 (GCVE-0-2026-110714)

Vulnerability from cvelistv5 – Published: 2026-10-14 15:01 – Updated: 2026-10-14 15:01
VLAI
Title
libsmb2 through 6.2 Heap Out-of-Bounds Read via decode_acl Integer Underflow
Summary
libsmb2 through 6.2 contains an integer underflow vulnerability in decode_acl that allows malicious SMB servers to trigger heap out-of-bounds reads via crafted security descriptors. Attackers controlling a server or intercepting unsigned sessions can send an AclSize below 8 in a QUERY_INFO reply, bypassing ACE bounds checks and crashing the client.
Severity
7.1 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
CWE
  • CWE-191 - Integer Underflow (Wrap or Wraparound)
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6249 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
sahlberg libsmb2 Affected: 0 , ≤ 6.2 (custom)
guessed Create a notification for this product.
Date Public
2026-07-10 00:00
Credits
韓佳翰 HaiND from the Post and Telecommunication Institute of Technology
Show details on NVD website
To clipboard 

{
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          "defaultStatus": "unaffected",
          "product": "libsmb2",
          "repo": "https://github.com/sahlberg/libsmb2",
          "vendor": "sahlberg",
          "versions": [
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              "status": "affected",
              "version": "0",
              "versionType": "custom"
            }
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          "type": "finder",
          "value": "\u97d3\u4f73\u7ff0"
        },
        {
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          "type": "finder",
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        }
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        }
      ],
      "metrics": [
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            "attackVector": "NETWORK",
            "baseScore": 7.1,
            "baseSeverity": "HIGH",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "PASSIVE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
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            "vulnIntegrityImpact": "NONE"
          },
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            "confidentialityImpact": "NONE",
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      "problemTypes": [
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              "description": "Integer Underflow (Wrap or Wraparound)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-14T15:01:29.077Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
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          "url": "https://hackmd.io/@haind-pwn/libsmb2-query-info-reply-oob-read"
        },
        {
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          ],
          "url": "https://github.com/sahlberg/libsmb2/blob/d67e213a5c4e7e4969fd81f0b95e4ca5831fbba1/lib/smb2-data-security-descriptor.c#L266"
        },
        {
          "tags": [
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          ],
          "url": "https://github.com/sahlberg/libsmb2/commit/523abe20be3207011a936db47f1d3bab79c05450"
        },
        {
          "tags": [
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          "url": "https://github.com/sahlberg/libsmb2"
        },
        {
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          "tags": [
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          ],
          "url": "https://www.vulncheck.com/advisories/libsmb2-through-6.2-heap-out-of-bounds-read-via-decode-acl-integer-underflow"
        }
      ],
      "title": "libsmb2 through 6.2 Heap Out-of-Bounds Read via decode_acl Integer Underflow",
      "x_generator": {
        "engine": "vulncheck-endgame"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-110714",
    "datePublished": "2026-10-14T15:01:29.077Z",
    "dateReserved": "2026-10-14T14:39:52.603Z",
    "dateUpdated": "2026-10-14T15:01:29.077Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-110714",
      "date": "2026-10-15",
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      "percentile": "0.44458"
    },
    "nvd": {
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            ],
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          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "libsmb2 through 6.2 contains an integer underflow vulnerability in decode_acl that allows malicious SMB servers to trigger heap out-of-bounds reads via crafted security descriptors. Attackers controlling a server or intercepting unsigned sessions can send an AclSize below 8 in a QUERY_INFO reply, bypassing ACE bounds checks and crashing the client."
          }
        ],
        "id": "CVE-2026-110714",
        "lastModified": "2026-10-14T16:17:43.473",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 6.5,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "REQUIRED",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H",
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          "cvssMetricV40": [
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                "Recovery": "NOT_DEFINED",
                "Safety": "NOT_DEFINED",
                "attackComplexity": "LOW",
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                "attackVector": "NETWORK",
                "availabilityRequirement": "NOT_DEFINED",
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                "baseSeverity": "HIGH",
                "confidentialityRequirement": "NOT_DEFINED",
                "exploitMaturity": "NOT_DEFINED",
                "integrityRequirement": "NOT_DEFINED",
                "modifiedAttackComplexity": "NOT_DEFINED",
                "modifiedAttackRequirements": "NOT_DEFINED",
                "modifiedAttackVector": "NOT_DEFINED",
                "modifiedPrivilegesRequired": "NOT_DEFINED",
                "modifiedSubAvailabilityImpact": "NOT_DEFINED",
                "modifiedSubConfidentialityImpact": "NOT_DEFINED",
                "modifiedSubIntegrityImpact": "NOT_DEFINED",
                "modifiedUserInteraction": "NOT_DEFINED",
                "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
                "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
                "modifiedVulnIntegrityImpact": "NOT_DEFINED",
                "privilegesRequired": "NONE",
                "providerUrgency": "NOT_DEFINED",
                "subAvailabilityImpact": "NONE",
                "subConfidentialityImpact": "NONE",
                "subIntegrityImpact": "NONE",
                "userInteraction": "PASSIVE",
                "valueDensity": "NOT_DEFINED",
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                "vulnerabilityResponseEffort": "NOT_DEFINED"
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        "references": [
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            "url": "https://github.com/sahlberg/libsmb2"
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            "url": "https://github.com/sahlberg/libsmb2/blob/d67e213a5c4e7e4969fd81f0b95e4ca5831fbba1/lib/smb2-data-security-descriptor.c#L266"
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    }
  }
}



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