CVE-2021-37840: Aapanel

High severity, CVSS 8.8. EPSS: 1.7% chance of exploitation in the next 30 days.

aaPanel through 6.8.12 allows Cross-Site WebSocket Hijacking (CSWH) involving OS commands within WebSocket messages at a ws:// URL for /webssh (the victim must have configured Terminal with at least one host). Successful exploitation depends on the browser used by a potential victim (e.g., exploitation can occur with Firefox but not Chrome).

Affected products

• Aapanel Aapanel: up to and including 6.8.12

Published 2021-08-02. Last modified 2026-06-17.