FKIE_CVE-2026-27171

Vulnerability from fkie_nvd - Published: 2026-02-18 04:16 - Updated: 2026-06-17 10:26
Severity
2.9 (Low) - CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Summary
zlib before 1.3.2 allows CPU consumption via crc32_combine64 and crc32_combine_gen64 because x2nmodp can do right shifts within a loop that has no termination condition.
References
cve@mitre.orghttps://7asecurity.com/blog/2026/02/zlib-7asecurity-audit/Product
cve@mitre.orghttps://7asecurity.com/reports/pentest-report-zlib-RC1.1.pdfTechnical Description
cve@mitre.orghttps://github.com/madler/zlib/issues/904Exploit, Issue Tracking
cve@mitre.orghttps://github.com/madler/zlib/releases/tag/v1.3.2Release Notes
cve@mitre.orghttps://ostif.org/zlib-audit-complete/Product
134c704f-9b21-4f2e-91b3-4a467353bcc0https://7asecurity.com/reports/pentest-report-zlib-RC1.1.pdfTechnical Description
Impacted products
Vendor Product Version
zlib zlib *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "zlib",
          "vendor": "zlib",
          "versions": [
            {
              "lessThan": "1.3.2",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "cve@mitre.org"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:zlib:zlib:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "94CCDD7A-18CD-4961-848E-A827A3E2F3BC",
              "versionEndExcluding": "1.3.2",
              "versionStartIncluding": "1.2.12",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "zlib before 1.3.2 allows CPU consumption via crc32_combine64 and crc32_combine_gen64 because x2nmodp can do right shifts within a loop that has no termination condition."
    },
    {
      "lang": "es",
      "value": "zlib anterior a 1.3.2 permite el consumo de CPU a trav\u00e9s de crc32_combine64 y crc32_combine_gen64 porque x2nmodp puede realizar desplazamientos a la derecha dentro de un bucle que no tiene condici\u00f3n de terminaci\u00f3n."
    }
  ],
  "id": "CVE-2026-27171",
  "lastModified": "2026-06-17T10:26:47.357",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "LOCAL",
          "availabilityImpact": "LOW",
          "baseScore": 2.9,
          "baseSeverity": "LOW",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L",
          "version": "3.1"
        },
        "exploitabilityScore": 1.4,
        "impactScore": 1.4,
        "source": "cve@mitre.org",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-27171",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-02-18T13:35:50.671404Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-02-18T04:16:01.263",
  "references": [
    {
      "source": "cve@mitre.org",
      "tags": [
        "Product"
      ],
      "url": "https://7asecurity.com/blog/2026/02/zlib-7asecurity-audit/"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Technical Description"
      ],
      "url": "https://7asecurity.com/reports/pentest-report-zlib-RC1.1.pdf"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Exploit",
        "Issue Tracking"
      ],
      "url": "https://github.com/madler/zlib/issues/904"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Release Notes"
      ],
      "url": "https://github.com/madler/zlib/releases/tag/v1.3.2"
    },
    {
      "source": "cve@mitre.org",
      "tags": [
        "Product"
      ],
      "url": "https://ostif.org/zlib-audit-complete/"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
        "Technical Description"
      ],
      "url": "https://7asecurity.com/reports/pentest-report-zlib-RC1.1.pdf"
    }
  ],
  "sourceIdentifier": "cve@mitre.org",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-1284"
        }
      ],
      "source": "cve@mitre.org",
      "type": "Secondary"
    }
  ]
}



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