CVE-2026-35389

HIGH

Bulwark Webmail S/MIME signature verification accepted self-signed certificates

Title source: cna

Description

Bulwark Webmail is a self-hosted webmail client for Stalwart Mail Server. Prior to 1.4.11, S/MIME signature verification did not validate the certificate trust chain (checkChain: false). Any email signed with a self-signed or untrusted certificate was displayed as having a valid signature. This vulnerability is fixed in 1.4.11.

References (1)

[X_Refsource_Confirm] https://github.com/bulwarkmail/webmail/security/advisories/GHSA-v6w6-338p-p256

Scores

CVSS v3 7.5

EPSS 0.0002

EPSS Percentile 6.2%

Attack Vector NETWORK

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CISA SSVC

Vulnrichment

Exploitation none

Automatable no

Technical Impact partial

Details

CWE

CWE-295

Status published

Products (1)

bulwarkmail/webmail < 1.4.11 (2 CPE variants)

Published Apr 06, 2026

Tracked Since Apr 07, 2026