A Business Logic vulnerability exists in SourceCodester Loan Management System v1.0 due to improper server-side validation. The application allows administrators to create "Loan Plans" with specific interest rates. While the frontend interface prevents users from entering negative numbers, this constraint is not enforced on the backend. An authenticated attacker can bypass the client-side restriction by manipulating the HTTP POST request to submit a negative value for the interest_percentage. This results in the creation of loan plans with negative interest rates.
Conclusion & alert: CVE-2026-30521 is rated Exploit Available (50/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.02%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
| EDB-ID | Source | Kind | Published | Link |
|---|---|---|---|---|
| — | nvd_ref | exploit_tag | Exploit-DB ↗ |
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-04-01 | — | 0.02% | — |
Full EPSS history (1 record total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 6.5 | 3.1 | MEDIUM |
|
2.8 | 3.6 | [email protected] |
| 6.5 | 3.1 | MEDIUM |
|
2.8 | 3.6 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| oretnom23 | loan_management_system | 1.0 | cpe:2.3:a:oretnom23:loan_management_system:1.0:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| https://github.com/meifukun/Web-Security-PoCs/blob/main/Loan-Management-System/BusinessLogic-LoanPlan-NegativeInterest.md | Exploit Third Party Advisory |