NN-2026:6-01

HTML injection in Schedule Restore Archive in Guardian/CMC before 26.1.0

Last update: 2026-05-19

Advisory IDNN-2026:6-01
TopicHTML injection in Schedule Restore Archive in Guardian/CMC before 26.1.0
CWE ImpactCWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Issue date2026-05-19
AffectsGuardian, CMC < v26.1.0
CVE Name(s)CVE-2025-40903
CVSS DetailsCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:L
CVSS Score4.8 (CVSS v4.0)
5.9 (CVSS v3.1)
CVE Risk LevelMedium (CVSS v4.0)
Medium (CVSS v3.1)
Risk Level for Nozomi customersLow

Summary

A Stored HTML Injection vulnerability was discovered in the Schedule Restore Archive functionality due to improper validation of an input parameter.

Impact

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.

Affected Products

Guardian, CMC < v26.1.0

Workarounds and Mitigations

Use internal firewall features to limit access to the web management interface. Review all accounts with administrative access to it and delete unnecessary ones.

Solutions

Upgrade to v26.1.0 or later.

Modification History

2026-05-19: Initial revision

Related Links

Acknowledgements

We thank the following parties for their efforts:

  • Stefano Libero, Andrea Palanca of Nozomi Networks Product Security team for finding this issue during an internal investigation

Contact

Nozomi Networks Product Security team can be reached at prodsec@nozominetworks.com.
More contact details on the PSIRT page.