CVE-2026-35389CWE-295

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

High · published April 6, 2026

CVSS v4.0
8.7
EPSS
0%
Percentile
13.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
8.7 · HIGH
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
EPSS
0.00236 · 13.7th percentile
Weakness
CWE-295 · Improper Certificate Validation
Published
2026-04-06T20:11Z
EPSS history
Timeline
  • 06 APR 20:11Z
    Bulwark Webmail S/MIME signature verification accepted self-signed certificates
    cvelistv5