PT-2026-30727 · Unknown · Bulwark Webmail+1

Richardweinberger · Published 2026-04-06 · Updated 2026-04-06 · CVE-2026-35389

Positive Technologies · (AI Summary)

CVSS v4.0

8.7

High

AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Name of the Vulnerable Software and Affected Versions Bulwark Webmail versions prior to 1.4.11

Description Bulwark Webmail, a self-hosted webmail client for Stalwart Mail Server, had an issue in S/MIME signature verification. Before version 1.4.11, the software did not validate the certificate trust chain during signature verification. This meant that emails signed with self-signed or untrusted certificates were incorrectly displayed as having valid signatures.

Recommendations Update to version 1.4.11 or later.

Fix

Improper Certificate Validation

Weakness Enumeration

CWE-295

Related Identifiers

CVE-2026-35389

Affected Products

Bulwark Webmail

Stalwart Mail Server

References · 4

• https://nvd.nist.gov/vuln/detail/CVE-2026-35389 · Security Note
• https://github.com/bulwarkmail/webmail/security/advisories/GHSA-v6w6-338p-p256 · Note
• https://twitter.com/CVEnew/status/2041260650069217392 · Twitter Post
• https://twitter.com/infoflowcloud/status/2041261120481091817 · Twitter Post