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, 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 v3 4.8 MEDIUM

4.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.2 / Impact : 3.6

Attack Vector ADJACENT_NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/ncalc/ncalc/commit/eeb6155ee1899b1fdf2cda3da35a4f0ca93ffd6a	Patch
https://github.com/ncalc/ncalc/pull/575	Issue Tracking Patch
https://github.com/ncalc/ncalc/releases/tag/v6.1.1	Product Release Notes
https://github.com/ncalc/ncalc/security/advisories/GHSA-3w5p-95mh-gq75	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:ncalc:ncalc:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-17 20:17

Updated : 2026-08-18 15:44

NVD link : CVE-2026-55254

Mitre link : CVE-2026-55254

CVE.ORG link : CVE-2026-55254

JSON object : View

Products Affected

ncalc

ncalc

CWE

CWE-190

Integer Overflow or Wraparound

CWE-770

Allocation of Resources Without Limits or Throttling

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