CVE-2026-29140
5.3 · MEDIUMOverview
CVE-2026-29140 is a medium-severity vulnerability affecting seppmail secure_email_gateway. It was published on April 2, 2026 and has a CVSS 3.1 base score of 5.3 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 5.3, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
SEPPmail Secure Email Gateway before version 15.0.3 allows an attacker to cause attacker-controlled certificates to be used for future encryption to a victim by adding the certificates to S/MIME signatures.
Remediation
Check the references section for vendor advisories and patches from seppmail. Update secure_email_gateway to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| seppmail | secure_email_gateway | >= 0, < 15.0.3 | Affected |
Frequently Asked Questions
What is CVE-2026-29140?
CVE-2026-29140 is a medium-severity vulnerability affecting seppmail secure_email_gateway. It was published on April 2, 2026 and has a CVSS 3.1 base score of 5.3 (MEDIUM).
How severe is CVE-2026-29140?
This vulnerability has a CVSS 3.1 base score of 5.3, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-29140?
Check the references section for vendor advisories and patches from seppmail. Update secure_email_gateway to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-29140?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-29140 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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