CVE-2026-35390
MediumCVSS 5.4Exploitation Probability (EPSS)
Low risk6th percentile - higher than 6% of all known CVEs
Summary
Bulwark Webmail prior to version 1.4.11 sets the Content-Security-Policy-Report-Only header instead of the enforcing Content-Security-Policy header. This means XSS attacks are logged but not blocked, allowing arbitrary JavaScript execution via crafted email HTML.
Risk Assessment
An attacker can steal session tokens or perform actions on behalf of the user, leading to full email account takeover.
Recommendation
Update Bulwark Webmail to version 1.4.11 or later.
Original NVD description (English source)
Bulwark Webmail is a self-hosted webmail client for Stalwart Mail Server. Prior to 1.4.11, the reverse proxy (proxy.ts) set the Content-Security-Policy-Report-Only header instead of the enforcing Content-Security-Policy header. This means cross-site scripting (XSS) attacks were logged but not blocked. Any user who could inject script content (e.g., via crafted email HTML) could execute arbitrary JavaScript in the context of the application, potentially stealing session tokens or performing actions on behalf of the user. This vulnerability is fixed in 1.4.11.