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.

CVSS v3 4.7 MEDIUM

4.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://security.nozominetworks.com/NN-2025:12-01	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:nozominetworks:cmc::::::::
	cpe:2.3:a:nozominetworks:guardian::::::::

History

06 Jan 2026, 20:11

Type	Values Removed	Values Added
References	~~() https://security.nozominetworks.com/NN-2025:12-01 -~~	() https://security.nozominetworks.com/NN-2025:12-01 - Vendor Advisory
First Time		Nozominetworks Nozominetworks guardian Nozominetworks cmc
CPE		cpe:2.3:a:nozominetworks:cmc:::::::: cpe:2.3:a:nozominetworks:guardian::::::::

18 Dec 2025, 14:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-12-18 14:15

Updated : 2026-01-06 20:11

NVD link : CVE-2025-40891

Mitre link : CVE-2025-40891

CVE.ORG link : CVE-2025-40891

JSON object : View

Products Affected

nozominetworks

cmc
guardian

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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