CVE-2026-84831 (GCVE-0-2026-84831)
Vulnerability from cvelistv5 – Published: 2026-09-03 08:43 – Updated: 2026-10-08 11:15
VLAI
EPSS
VEX
Title
Mandatory MFA bypass before enrollment
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-03 12:34 UTC
Assigner
References
1 reference
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| SEPPmail AG | SEPPmail Secure Email Gateway (SEG) |
Affected:
0 , < 15.0.7
(custom)
|
guessed |
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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