PatchTheCVECVE-2026-29140: SEPPmail Secure Email Gateway before version 15.0.3 allows an attacker to cause attacker-controlled certificat
CVE-2026-29140 is a medium-severity flaw (CVSS 5.3) affecting secure email gateway. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
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.
Why this priority
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 5.3 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.1% (top 98%) |
| CISA exploited list | No |
| Weakness | CWE-295 |
| Published | 2026-04-02 |
| Last modified | 2026-10-26 |
Last updated 2026-10-26 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-29140?
secure email gateway: upgrade to 15.0.3. Exact commands for each OS are on this page.
Is CVE-2026-29140 being exploited?
CVE-2026-29140 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-29140 affect?
CVE-2026-29140 affects secure email gateway. Severity is medium (CVSS 5.3). 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.
How urgent is CVE-2026-29140?
Priority 24/100. Remotely exploitable, no login, no user action
Related CVEs
- CVE-2026-29139 CRITICAL 9.8 UPGRADE SEPPmail Secure Email Gateway before version 15.0.3 allows account takeover by abusing GINA account initializa
- CVE-2026-29143 CRITICAL 9.1 UPGRADE SEPPmail Secure Email Gateway before version 15.0.3 does not properly authenticate the inner message of S/MIME
- CVE-2026-29133 CRITICAL 9.1 UPGRADE SEPPmail Secure Email Gateway before version 15.0.3 allows an attacker to upload PGP keys with UIDs that do no
- CVE-2026-29131 HIGH 7.5 UPGRADE SEPPmail Secure Email Gateway before version 15.0.3 allows attackers with a specially crafted email address to
- CVE-2026-29132 HIGH 7.5 UPGRADE SEPPmail Secure Email Gateway before version 15.0.3 allows an attacker with access to a victim's GINA account