What is CVE-2026-64637?

CVE-2026-64637 is a critical-severity vulnerability in Webpros Plesk, classified under Improper Privilege Management. CVSS score: 9.9/10. Published 2026-08-07.

How severe is CVE-2026-64637?

Critical severity. CVSS v3 base score is 9.9 out of 10.

Privilege escalation in Webpros Plesk

CVE-2026-64637

Improper privilege management in the XML-RPC API of Plesk before 18.0.80, allows an authenticated reseller to obtain an administrative session for the root user account.

Vulnerability class: Privilege Escalation

CVSS v3 metric

CVSS v3 base score 9.9 (Critical). Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.

Affected products

Webpros Plesk — versions 0

Weakness classification (CWE)

CWE-269 — Improper Privilege Management

References

support@hackerone.com

Frequently asked questions

What is CVE-2026-64637?: CVE-2026-64637 is a critical-severity vulnerability in Webpros Plesk, classified under Improper Privilege Management. CVSS score: 9.9/10. Published 2026-08-07.
How severe is CVE-2026-64637?: Critical severity. CVSS v3 base score is 9.9 out of 10.