Bulwark Webmail S/MIME signature verification accepted self-signed certificates
Priority LOW 37CWE-295Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Spoofing
- Confidentiality · integrity · availability
- None · High · None
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-295.
Summary
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.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00181 7th percentileScored 2026-11-07
Fix Fixed webmail (bulwarkmail): 1.4.11
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| bulwarkmail | webmail | before 1.4.11 | 1.4.11 | Patch available | CNA |
- webmail Vendorbulwarkmail Affected before 1.4.11 Fixed in 1.4.11 Patch available CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:bulwarkmail:webmail:*:*:*:*:*:*:*:* | before 1.4.11 | Vulnerable | bulwarkmail |
- cpe:2.3:a:bulwarkmail:webmail:*:*:*:*:*:*:*:* Versions before 1.4.11 Vulnerable ·bulwarkmail
Remediation
- Fix · CNA webmail (bulwarkmail) Fixed in 1.4.11
Timeline
- 2026-10-02 Threatist record created from CVE-2026-35389
References
More bulwarkmail Webmail vulnerabilities
- TI-2026-27078 Bulwark Webmail: Authentication Bypass in verifyIdentity() due to missing cookie validation CVSS 4.0HIGH 8.7
- TI-2026-27077 Bulwark Webmail: Information Exposure: password returned in /api/auth/session CVSS 4.0HIGH 8.7
- TI-2026-27527 Bulwark Webmail getClientIP() trusted client-controlled X-Forwarded-For value, enabling… CVSS 4.0HIGH 8.7
- TI-2026-27526 Content-Security-Policy was set to Report-Only mode, failing to block XSS attacks CVSS 4.0MEDIUM 5.3
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences