CVE-2025-40899 Stored Cross-Site Scripting (XSS) in Assets and Nodes in Guardian/CMC before 26.0.0
Authenticated users can inject malicious scripts via custom fields, allowing attackers to execute code in victims' browsers to modify data or access information.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2025-40899?
CVE-2025-40899 is a high-severity cross-site scripting vulnerability in Nozomi Networks CMC, published on 15 Apr 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
A Stored Cross-Site Scripting vulnerability was discovered in the Assets and Nodes functionality due to improper validation of an input parameter. An authenticated user with custom fields privileges can define a malicious custom field containing a JavaScript payload. When the victim views the Assets or Nodes pages, the XSS executes in their browser context, allowing the attacker to perform unauthorized actions as the victim, such as modify application data, disrupt application availability, and access limited sensitive information.
Weakness: CWE-79
Which versions are affected by CVE-2025-40899?
How do I fix CVE-2025-40899?
No fix has been published for CVE-2025-40899 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2025-40899 being exploited?
There is no known exploitation of CVE-2025-40899 in the wild and no public exploit code.
Sources
Also known as GHSA-28p4-5j5m-924h.