CVE-2026-31981 HTML injection in Diagram tab and Graph view in Guardian/CMC before 26.2.0
Authenticated administrators can inject HTML into configuration data, enabling phishing or open redirects when viewed by others in the web interface.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-31981?
CVE-2026-31981 is a medium-severity cross-site scripting vulnerability in Nozomi Networks CMC, published on 9 Jul 2026. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.
Official description
A Stored HTML Injection vulnerability was discovered in the Diagram tab and Graph view due to a shared input validation function being insufficiently restrictive. An authenticated user with administrative privileges can inject malicious HTML tags into N2OS configuration data through multiple input vectors. When a victim views the affected data in the Diagram tab and Graph view, 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.
Weakness: CWE-79
Which versions are affected by CVE-2026-31981?
It affects 2 products.
Products include Nozominetworks Cmc, Nozominetworks Guardian.
How do I fix CVE-2026-31981?
No fix has been published for CVE-2026-31981 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-2026-31981 being exploited?
There is no known exploitation of CVE-2026-31981 in the wild and no public exploit code.
Other vulnerabilities in Nozomi Networks CMC
- CVE-2023-29245 SQL Injection on IDS parsing of malformed asset fields in Guardian/CMC >= 22.6.0 before 22.6.3 and 23.1.0
- CVE-2026-31984 DoS through oversized audit log entries in Guardian/CMC before 26.2.0
- CVE-2023-2567 Authenticated SQL Injection on Query functionality in Guardian/CMC before 22.6.3 and 23.1.0
- CVE-2023-22378 Authenticated Blind SQL Injection on sorting in Guardian/CMC before 22.6.2
- CVE-2023-23574 Authenticated Blind SQL Injection on alerts count in Guardian/CMC before 22.6.2
Sources
Also known as GHSA-5g4m-c643-h8fj.