CVE-2026-35391: Bulwarkmail Webmail

High severity, CVSS 7.5. EPSS: 0.2% chance of exploitation in the next 30 days.

Bulwark Webmail is a self-hosted webmail client for Stalwart Mail Server. Prior to 1.4.11, the getClientIP() function in lib/admin/session.ts trusted the first (leftmost) entry of the X-Forwarded-For header, which is fully controlled by the client. An attacker could forge their source IP address to bypass IP-based rate limiting (enabling brute-force attacks against the admin login) or forge audit log entries (making malicious activity appear to originate from arbitrary IP addresses). This vulnerability is fixed in 1.4.11.

Affected products

Published 2026-04-06. Last modified 2026-07-24.