CVE-2023-5771: Proofpoint Enterprise Protection

Medium severity, CVSS 6.1. EPSS: 0.3% chance of exploitation in the next 30 days.

Proofpoint Enterprise Protection contains a stored XSS vulnerability in the AdminUI. An unauthenticated attacker can send a specially crafted email with HTML in the subject which triggers XSS when viewing quarantined messages.  This issue affects Proofpoint Enterprise Protection: from 8.20.0 before patch 4796, from 8.18.6 before patch 4795 and all other prior versions.

Affected products

• Proofpoint Enterprise Protection: before 8.18.6 (fixed in 8.18.6); version 8.18.6 only; version 8.20.0 only

Published 2023-11-06. Last modified 2026-06-17.