CVE-2025-40902

HTML injection in Users in Guardian/CMC before 26.1.0

MEDIUM
4.8
CVSS Score
Published: May 19, 2026 at 01:21 PM UTC
Updated: October 14, 2026 at 01:10 PM UTC
3 products affected across 2 vendorsGuardianCMCRUGGEDCOM APE1808 Firmware

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Severity
MEDIUM4.8
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

Description

A Stored HTML Injection vulnerability was discovered in the Users functionality due to improper validation of an input parameter. An authenticated user with administrative privileges can create a malicious user whose username contains HTML tags. When a victim attempts to delete a group containing the affected user, 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

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

All versionsv < 26.1.0
Affected range stops below 26.1.0, so it looks safe — our inference, not a vendor statement
All versionsv < 26.1.0
Affected range stops below 26.1.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (2)

Vendor Advisory
Source: cverecord
https://security.nozominetworks.com/NN-2026:5-01
Source: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
https://cert-portal.siemens.com/productcert/html/ssa-827968.html

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

4.8MEDIUMNozomi
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-79

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