How severe is CVE-2026-30521?

CVE-2026-30521 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2026-30521 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-30521?

CVE-2026-30521 affects Oretnom23 Loan Management System. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-30521?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-30521 have an EU (EUVD) identifier?

Yes. CVE-2026-30521 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17583.

When was CVE-2026-30521 published?

CVE-2026-30521 was published on 2026-03-31 and last updated on 2026-06-17.

CVE-2026-30521

CVE-2026-30521 is a medium-severity vulnerability in Oretnom23 Loan Management System with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-602.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 0% (23rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-17583
Weakness: CWE-602
Affected product: Oretnom23 Loan Management System
Published: 2026-03-31
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2026-30521?: 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.
How severe is CVE-2026-30521?: CVE-2026-30521 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2026-30521 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-30521?: CVE-2026-30521 affects Oretnom23 Loan Management System. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-30521?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-30521 have an EU (EUVD) identifier?: Yes. CVE-2026-30521 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17583.
When was CVE-2026-30521 published?: CVE-2026-30521 was published on 2026-03-31 and last updated on 2026-06-17.

References

https://github.com/meifukun/Web-Security-PoCs/blob/main/Loan-Management-System/BusinessLogic-LoanPlan-NegativeInterest.md

Affected products (1)

cpe:2.3:a:oretnom23:loan_management_system:1.0:*:*:*:*:*:*:*

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