FKIE_CVE-2026-55254

Vulnerability from fkie_nvd - Published: 2026-07-17 20:17 - Updated: 2026-07-17 20:17
Severity
4.8 (Medium) - CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H
Summary
NCalc is a fast, lightweight expression evaluator for .NET. Prior to 6.1.1, the factorial operator implementation in src/NCalc.Core/Helpers/MathHelper.cs permits specially crafted expressions with extremely large factorial operands, causing excessive CPU consumption or a non-terminating loop due to integer overflow in the factorial calculation logic when applications evaluate untrusted expressions. This issue is fixed in version 6.1.1.
References
security-advisories@github.comhttps://github.com/ncalc/ncalc/commit/eeb6155ee1899b1fdf2cda3da35a4f0ca93ffd6a
security-advisories@github.comhttps://github.com/ncalc/ncalc/pull/575
security-advisories@github.comhttps://github.com/ncalc/ncalc/releases/tag/v6.1.1
security-advisories@github.comhttps://github.com/ncalc/ncalc/security/advisories/GHSA-3w5p-95mh-gq75
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "ncalc",
          "vendor": "ncalc",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 6.1.1"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "NCalc is a fast, lightweight expression evaluator for .NET. Prior to 6.1.1, the factorial operator implementation in src/NCalc.Core/Helpers/MathHelper.cs permits specially crafted expressions with extremely large factorial operands, causing excessive CPU consumption or a non-terminating loop due to integer overflow in the factorial calculation logic when applications evaluate untrusted expressions. This issue is fixed in version 6.1.1."
    }
  ],
  "id": "CVE-2026-55254",
  "lastModified": "2026-07-17T20:17:27.023",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "ADJACENT_NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 4.8,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.2,
        "impactScore": 3.6,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-07-17T20:17:27.023",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/ncalc/ncalc/commit/eeb6155ee1899b1fdf2cda3da35a4f0ca93ffd6a"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/ncalc/ncalc/pull/575"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/ncalc/ncalc/releases/tag/v6.1.1"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/ncalc/ncalc/security/advisories/GHSA-3w5p-95mh-gq75"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-190"
        },
        {
          "lang": "en",
          "value": "CWE-770"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Primary"
    }
  ]
}



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