Integer overflow in Ncalc

CVE-2026-55254

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, causin…

Vulnerability class: Integer Overflow

CVSS v3 metric

CVSS v3 base score 4.8 (Medium). Vector: CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H.

Affected products

  • Ncalc — versions < 6.1.1

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-55254?
CVE-2026-55254 is a medium-severity vulnerability in Ncalc, classified under Integer Overflow or Wraparound. CVSS score: 4.8/10. Published 2026-07-17.
How severe is CVE-2026-55254?
Medium severity. CVSS v3 base score is 4.8 out of 10.