What is CVE-2026-29139?

CVE-2026-29139 is a critical-severity vulnerability in Seppmail Secure Email Gateway, classified under Authentication Bypass Using an Alternate Path or Channel. CVSS score: 9.8/10. Published 2026-04-02.

How severe is CVE-2026-29139?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Vulnerability in Seppmail Secure Email Gateway

CVE-2026-29139

SEPPmail Secure Email Gateway before version 15.0.3 allows account takeover by abusing GINA account initialization to reset a victim account password.

EPSS: 0.003 (19.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Seppmail Secure Email Gateway — versions 0
Seppmail Secure_email_gateway

Weakness classification (CWE)

CWE-288 — Authentication Bypass Using an Alternate Path or Channel

References

vulnerability@ncsc.ch (release-notes, Release Notes)

Frequently asked questions

What is CVE-2026-29139?: CVE-2026-29139 is a critical-severity vulnerability in Seppmail Secure Email Gateway, classified under Authentication Bypass Using an Alternate Path or Channel. CVSS score: 9.8/10. Published 2026-04-02.
How severe is CVE-2026-29139?: Critical severity. CVSS v3 base score is 9.8 out of 10.