bulwarkmail webmail up to 1.4.10 SMIME Signature Verification certificate validation

CVSS Meta Temp Score
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CTI Interest Score
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3.6$0-$5k1.03+

Summaryinfo

A vulnerability classified as critical was found in bulwarkmail webmail up to 1.4.10. The impacted element is an unknown function of the component SMIME Signature Verification. Such manipulation leads to certificate validation. This vulnerability is referenced as CVE-2026-35389. It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in bulwarkmail webmail up to 1.4.10. It has been rated as problematic. Affected by this issue is an unknown function of the component SMIME Signature Verification. The manipulation with an unknown input leads to a certificate validation vulnerability. Using CWE to declare the problem leads to CWE-295. The product does not validate, or incorrectly validates, a certificate. Impacted is integrity. CVE summarizes:

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 advisory is available at github.com. This vulnerability is handled as CVE-2026-35389 since 04/02/2026. The exploitation is known to be difficult. The attack may be launched remotely. No form of authentication is required for exploitation. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1587.003 by the MITRE ATT&CK project.

Upgrading to version 1.4.11 eliminates this vulnerability.

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Productinfo

Type

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 3.7
VulDB Meta Temp Score: 3.6

VulDB Base Score: 3.7
VulDB Temp Score: 3.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Certificate validation
CWE: CWE-295 / CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: webmail 1.4.11

Timelineinfo

04/02/2026 CVE reserved
04/06/2026 +4 days Advisory disclosed
04/06/2026 +0 days VulDB entry created
04/06/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-35389 (🔒)
GCVE (CVE): GCVE-0-2026-35389
GCVE (VulDB): GCVE-100-355670

Entryinfo

Created: 04/06/2026 22:41
Changes: 04/06/2026 22:41 (68)
Complete: 🔍
Cache ID: 216:7F3:103

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