# CVE-2025-40902: Nozomi Networks Guardian and CMC HTML injection in Users functionality

Source: https://junglewise.ai/threats/cve-2025-40902-nozomi-networks-guardian-and-cmc-html-injection-in-users  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-19. Updated: 2026-05-19  
License: CC BY 4.0 with a link back

CVE-2025-40902 · Severity: medium · CVSS 5.9 · Published 2026-05-19

Nozomi Networks Guardian and CMC, which are used for industrial cybersecurity and network monitoring, are affected by a security flaw in their user management interface. An administrative user can create a specially crafted username that triggers malicious code in the browser of another administrator when they attempt to delete certain groups. While existing security measures prevent full system takeover, this could be used for phishing or redirecting staff to malicious websites.

Technologies: [Nozomi Networks Central Management Console](https://junglewise.ai/threats/technologies/central-management-console), [Nozomi Networks Guardian](https://junglewise.ai/threats/technologies/guardian). Vendors: [Nozomi Networks](https://junglewise.ai/threats/vendors/nozomi-networks).

## Quick answers

**Is CVE-2025-40902 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-40902 being exploited in the wild.

**How severe is CVE-2025-40902?** Medium severity, with a CVSS score of 5.9, published 19 May 2026.

**Which products and versions are affected?** Nozomi Networks Central Management Console < 26.1.0; Nozomi Networks Guardian < 26.1.0.

**Is there a fix for CVE-2025-40902?** A patch was published on 2026-05-19: Fixed in version 26.1.0 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2025-40902 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2025-40902?** Check whether you run Nozomi Networks Central Management Console or Nozomi Networks Guardian at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A stored HTML injection vulnerability exists in the Users functionality of Nozomi Networks Guardian and CMC due to improper validation of the username input parameter. An authenticated attacker with administrative privileges can create a user with a name containing HTML tags. This payload is executed in the context of another user's browser when they perform specific actions, such as attempting to delete a group containing the malicious user. While the platform's Content Security Policy (CSP) and existing input validation prevent full Cross-Site Scripting (XSS) and direct data exfiltration, the flaw can be leveraged for phishing or open redirect attacks. The issue is resolved in version 26.1.0.

## Affected products

- Nozomi Networks Guardian < 26.1.0
- Nozomi Networks Central Management Console (CMC) < 26.1.0

## Timeline

- 2026-05-19: disclosed
- 2026-05-19: patched: Fixed in version 26.1.0
- 2026-05-19: advisory

## References

- [https://security.nozominetworks.com/NN-2026:5-01](https://security.nozominetworks.com/NN-2026:5-01)

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