What is the CVSS score of CVE-2026-30558?

CVE-2026-30558 has a CVSS 3.1 base score of 6.1 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N. EPSS exploitation probability: 0.1%.

Is there a public PoC exploit available for CVE-2026-30558?

Yes, a public proof-of-concept exploit is available for CVE-2026-30558. Prioritise patching immediately. EPSS: 0.1%.

PHP CVE-2026-30558

EUVD-2026-17097 MEDIUM

Cross-site Scripting (XSS) (CWE-79)

2026-03-30 mitre

GHSA-xcvp-qwq2-j64h

XSS PHP

6.1

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

6.1 MEDIUM

AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Lifecycle Timeline

PoC Detected

Apr 06, 2026 - 14:16 vuln.today

Public exploit code

EUVD ID Assigned

Mar 30, 2026 - 16:00 euvd

EUVD-2026-17097

Analysis Generated

Mar 30, 2026 - 16:00 vuln.today

CVE Published

Mar 30, 2026 - 00:00 nvd

MEDIUM 6.1

DescriptionCVE.org

A Reflected Cross-Site Scripting (XSS) vulnerability exists in SourceCodester Sales and Inventory System 1.0. The vulnerability is located in the add_customer.php file via the "msg" parameter. The application fails to sanitize the input, allowing remote attackers to inject arbitrary web script or HTML via a crafted URL.

AnalysisAI

Reflected cross-site scripting in SourceCodester Sales and Inventory System 1.0 allows remote attackers to inject arbitrary JavaScript or HTML through an unsanitized 'msg' parameter in add_customer.php, enabling session hijacking, credential theft, or malware distribution via crafted URLs. Publicly available exploit code exists demonstrating the vulnerability.

Technical ContextAI

The vulnerability is a classic reflected XSS flaw (CWE category: improper neutralization of input during web page generation) in a PHP-based inventory management application. The add_customer.php endpoint accepts user-supplied input via the 'msg' query parameter and reflects it into the HTML response without proper encoding or sanitization. When a victim visits a malicious URL containing JavaScript payload in the 'msg' parameter, the browser executes the injected code in the context of the vulnerable application, bypassing same-origin protections if the application shares sensitive domains or cookies. This is a server-side input validation failure compounded by lack of output encoding (e.g., missing htmlspecialchars() or equivalent escaping in PHP).

RemediationAI

Immediately upgrade to a patched version if available from SourceCodester, or apply immediate input/output controls: (1) Sanitize the 'msg' parameter on server-side using PHP's htmlspecialchars() with ENT_QUOTES flag before outputting to HTML, or use a templating engine with automatic escaping; (2) Implement output encoding for all user-controlled data reflected in responses; (3) Deploy a Content Security Policy (CSP) header to restrict inline script execution; (4) Enable HttpOnly and Secure flags on session cookies to prevent JavaScript access. For production systems, consider migrating to a maintained inventory platform, as SourceCodester projects are educational tools. Reference: GitHub PoC available at https://github.com/meifukun/Web-Security-PoCs/blob/main/Inventory-System/XSS-AddCustomer-msg.md documents the exact exploitation method.