Vulnerability Description
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.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Ncalc | Ncalc | < 6.1.1 |
Related Weaknesses (CWE)
References
- https://github.com/ncalc/ncalc/commit/eeb6155ee1899b1fdf2cda3da35a4f0ca93ffd6aPatch
- https://github.com/ncalc/ncalc/pull/575Issue TrackingPatch
- https://github.com/ncalc/ncalc/releases/tag/v6.1.1ProductRelease Notes
- https://github.com/ncalc/ncalc/security/advisories/GHSA-3w5p-95mh-gq75PatchVendor Advisory
FAQ
What is CVE-2026-55254?
CVE-2026-55254 is a vulnerability with a CVSS score of 4.8 (MEDIUM). 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 ext...
How severe is CVE-2026-55254?
CVE-2026-55254 has been rated MEDIUM with a CVSS base score of 4.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-55254?
Check the references section above for vendor advisories and patch information. Affected products include: Ncalc Ncalc.