7.7
HIGH CVSS 4.0
CVE-2026-84831
Mandatory MFA bypass before enrollment
Description

SEPPmail Secure Email Gateway before 15.0.7 creates a fully privileged session before required multi-factor authentication enrollment is completed. An attacker with the password for an MFA-required but unenrolled account can access protected functionality without providing a second factor.

INFO

Published Date :

Sept. 3, 2026, 8:43 a.m.

Last Modified :

Sept. 3, 2026, 8:43 a.m.

Remotely Exploit :

Yes !

Source :

NCSC.ch
Affected Products

The following products are affected by CVE-2026-84831 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Seppmail secure_email_gateway
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 HIGH 455daabc-a392-441d-aa46-37d35189897c
Solution
Apply updates to enforce multi-factor authentication before granting access.
  • Update SEPPmail Secure Email Gateway to version 15.0.7 or later.
  • Ensure MFA enrollment is completed before session creation.
  • Review account access policies for compliance.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-84831 vulnerability anywhere in the article.

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.