CVE-2026-35390
CWE-79Published: April 6, 2026· Updated: Apr 9, 2026
Official Description
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.
Technical Analysis
CVE-2026-35390 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.
From a weakness classification perspective (CWE-79): Cross-site scripting (XSS) vulnerabilities allow attackers to inject malicious scripts into web pages viewed by other users.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (1)
Quick Facts
Related CVEs (CWE-79)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-35390 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts