CVE-2026-35390

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.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.3 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/bulwarkmail/webmail/security/advisories/GHSA-6q52-98cr-qx65	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:bulwarkmail:webmail:*:*:*:*:*:*:*:*

History

09 Apr 2026, 20:49

Type	Values Removed	Values Added
CPE		cpe:2.3:a:bulwarkmail:webmail::::::::
CVSS	v2 : ~~unknown~~ v3 : ~~6.1~~	v2 : unknown v3 : 5.4
References	~~() https://github.com/bulwarkmail/webmail/security/advisories/GHSA-6q52-98cr-qx65 -~~	() https://github.com/bulwarkmail/webmail/security/advisories/GHSA-6q52-98cr-qx65 - Vendor Advisory
First Time		Bulwarkmail webmail Bulwarkmail

07 Apr 2026, 20:16

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 6.1

06 Apr 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-06 21:16

Updated : 2026-04-09 20:49

NVD link : CVE-2026-35390

Mitre link : CVE-2026-35390

CVE.ORG link : CVE-2026-35390

JSON object : View

Products Affected

bulwarkmail

webmail

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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