CVE-2021-42080: Osnexus Quantastor

High severity, CVSS 7.4. EPSS: 0.7% chance of exploitation in the next 30 days.

An attacker is able to launch a Reflected XSS attack using a crafted URL. POC: Visit the following URL https://<IPADDRESS>:8153/qstorapi/echo?inputMessage=<img%20src=x%20onerror=alert(document.cookie)>

Affected products

• Osnexus Quantastor: before 6.0.0.355 (fixed in 6.0.0.355)

Published 2023-07-10. Last modified 2026-06-17.