Is CVE-2021-35489 actively exploited?

No active exploitation of CVE-2021-35489 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2021-35489 be exploited remotely?

Yes. CVE-2021-35489 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2021-35489?

CVE-2021-35489 has a CVSS score of 6.1 (MEDIUM).

HOME VULNERABILITIESCVE-2021-35489

MEDIUM

CVE-2021-35489

CWE-79Published: November 9, 2021· Updated: Jun 17, 2026

6.1

CVSS v3.1

Official Description

Thruk 2.40-2 allows /thruk/#cgi-bin/extinfo.cgi?type=2&host={HOSTNAME]&service={SERVICENAME]&backend={BACKEND] Reflected XSS via the host or service parameter. An attacker could inject arbitrary JavaScript into extinfo.cgi. The malicious payload would be triggered every time an authenticated user browses the page containing it.

NVD Source

Technical Analysis

CVE-2021-35489 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation does not require any privileges, though user interaction (Required) is needed, which slightly reduces the risk of mass automated attacks.

The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.

From a weakness classification perspective (CWE-79): Cross-site scripting (XSS) vulnerabilities allow attackers to inject malicious scripts into web pages viewed by other users.