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CVE-2026-103634

Full vulnerability record from the local CVENow database.

Description

Out-of-bounds read and write in the Count-Min sketch deserialization of Apache DataSketches C++ (repo: datasketches-cpp). count_min_sketch::deserialize() did not include the preamble in its input size check, so a truncated sketch could cause a read of up to 16 bytes past the end of the input. In addition, the table size was computed from the serialized number of buckets and number of hash functions in 32-bit arithmetic. A crafted sketch could make it wrap to zero, so that the sketch deserialized with an empty table, and later updates and estimate queries read and wrote outside the heap allocation. This can corrupt heap memory, causing a crash and potentially enabling further exploitation. This issue affects Apache DataSketches C++: from 4.1.0 before 5.3.0. Only applications that deserialize Count-Min sketches from untrusted sources are affected. Users are recommended to upgrade to version 5.3.0, which fixes this issue.

Severity
MEDIUM
CVSS score
5.3 (v3.1)
Vulnerability status
Awaiting Analysis
Source identifier
Published
2026-10-22 07:16:40.783000
Last modified
2026-10-26 14:16:23.527000
View original CVE JSON
{
  "id": "CVE-2026-103634",
  "sourceIdentifier": "[email protected]",
  "published": "2026-10-22T07:16:40.783",
  "lastModified": "2026-10-26T14:16:23.527",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Out-of-bounds read and write in the Count-Min sketch deserialization of Apache DataSketches C++ (repo: datasketches-cpp).\n\ncount_min_sketch::deserialize() did not include the preamble in its input size check, so a truncated sketch could cause a read of up to 16 bytes past the end of the input. In addition, the table size was computed from the serialized number of buckets and number of hash functions in 32-bit arithmetic. A crafted sketch could make it wrap to zero, so that the sketch deserialized with an empty table, and later updates and estimate queries read and wrote outside the heap allocation. This can corrupt heap memory, causing a crash and potentially enabling further exploitation.\n\nThis issue affects Apache DataSketches C++: from 4.1.0 before 5.3.0. Only applications that deserialize Count-Min sketches from untrusted sources are affected.\n\nUsers are recommended to upgrade to version 5.3.0, which fixes this issue."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "Apache Software Foundation",
          "product": "Apache DataSketches",
          "defaultStatus": "unaffected",
          "collectionURL": "https://github.com",
          "packageName": "apache/datasketches-cpp",
          "packageURL": "pkg:github/apache/datasketches-cpp",
          "versions": [
            {
              "version": "4.1.0",
              "lessThanOrEqual": "5.2.0",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "LOW"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 1.4
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-10-26T13:43:10.294464Z",
          "id": "CVE-2026-103634",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-190"
        },
        {
          "lang": "en",
          "value": "CWE-787"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/apache/datasketches-cpp/releases/tag/5.3.0",
      "source": "[email protected]"
    },
    {
      "url": "https://lists.apache.org/thread/rkx9oh06g5cjc6vmmpqloxwfz0gzz01h",
      "source": "[email protected]"
    },
    {
      "url": "http://www.openwall.com/lists/oss-security/2026/10/10/4",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    }
  ]
}