XSS in Nozomi Networks Cmc

CVE-2025-40891

A Stored HTML Injection vulnerability was discovered in the Time Machine Snapshot Diff functionality due to improper validation of network traffic data. An unauthenticated attacker can send specially crafted network packets at two different times to inject HTML tags into asset attributes across two snapshots. Exploitation requires a victim to use the Time Machine Snapshot Diff feature on those specific snapshots and perform specific GUI actions, at which point the injected HTML renders in their browser, enabling phishing and open redirect attacks. Full XSS exploitation is prevented by input validation and Content Security Policy. Attack complexity is high due to multiple required conditions.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.001 (4.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.7 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-40891?
CVE-2025-40891 is a medium-severity vulnerability in Nozomi Networks Cmc, classified under Cross-site Scripting. CVSS score: 4.7/10. Published 2025-12-18.
How severe is CVE-2025-40891?
Medium severity. CVSS v3 base score is 4.7 out of 10.