CVE-2026-55254 | BDVDB-2026-349261 Detail

ncalcncalc

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.

Impact#

Per CVSS v3.1: confidentiality impact none, integrity impact none, availability impact high. Attack vector: adjacent.

Weaknesses#

CWE-770 Allocation of Resources Without Limits or Throttling
CWE-190 Integer Overflow or Wraparound

References#

Exploit#

No public exploit known

History#

Version 12026-07-17Record published in the CVE List.
Version 22026-07-20Most recent update recorded in the CVE List.

Published

Published: 2026-07-17
Last modified: 2026-07-20

Vendor information

Vendor: ncalc
Product: ncalc

All ncalc vulnerabilities

Score

4.8 Medium

EPSS

less than 1%, Very Low

Estimated chance of exploitation in the next 30 days. EPSS percentile: 21.9.

KEV

Not listed in the CISA Known Exploited Vulnerabilities catalog.

Impact

Memory Corruption

Action

No specific action is recorded in the source data. Check the references for vendor guidance.

Affected Systems

Vulnerable
< 6.1.1
Fixed
Not stated

Scoring System

CVSS v4.0

Not available

CVSS v3.1

4.8 Medium

CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H

Metric breakdown
Attack Vector	Adjacent
Attack Complexity	High
Privileges Required	None
User Interaction	Required
Scope	Unchanged
Confidentiality	None
Integrity	None
Availability	High

CVSS v3.0

Not available

CVSS v2

Not available

Source: CVE List v5 (record); CISA KEV (kev, action); FIRST EPSS (epss).