Description
A Business Logic vulnerability exists in SourceCodester Loan Management System v1.0 due to the lack of proper input validation. The application allows administrators to define "Loan Plans" which determine the duration of a loan (in months). However, the backend fails to validate that the duration must be a positive integer. An attacker can submit a negative value for the months parameter. The system accepts this invalid data and creates a loan plan with a negative duration.
Affected products
oretnom23: loan management system
References1
- github.com/meifukun/Web-Security-PoCs/blob/main/Loan-Management… ExploitThird Party Advisory
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H - EPSS — exploit probability
- 0% percentile: 25 · as of 12 November 2026
- CWE
- CWE-20
Could this be exploited in your environment?
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