EUVD-2026-18146
GHSA-g982-ffmg-jq3g
Severity by source
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
Lifecycle Timeline
4DescriptionCVE.org
SEPPmail Secure Email Gateway before version 15.0.3 allows an attacker to upload PGP keys with UIDs that do not match their email address.
AnalysisAI
SEPPmail Secure Email Gateway before version 15.0.3 allows attackers to upload PGP keys with mismatched User IDs and email addresses, enabling spoofing and potential information disclosure by circumventing email authentication controls. The vulnerability affects all versions prior to 15.0.3 and was reported by NCSC.ch. No public exploit code or active exploitation has been confirmed at the time of analysis.
Technical ContextAI
SEPPmail Secure Email Gateway is an email security appliance that manages PGP key infrastructure for encrypted communications. The vulnerability stems from insufficient input validation (CWE-20: Improper Input Validation) in the PGP key upload mechanism. The system fails to enforce consistency between a PGP key's User ID (UID) field and the actual email address associated with that key in the gateway's trust store. PGP UIDs are metadata fields within a key that typically identify the key owner; when these can be mismatched with registered email addresses, attackers can create keys that appear to belong to legitimate senders while actually being under attacker control. This undermines the core security model of PGP-based secure email by breaking the binding between identity assertion and cryptographic key ownership.
RemediationAI
Vendor-released patch: SEPPmail Secure Email Gateway version 15.0.3 or later. Organizations should immediately upgrade to version 15.0.3 to enforce proper validation of PGP key UIDs against registered email addresses. After patching, administrators should audit existing PGP keys in the gateway trust store to identify and remove any keys with mismatched UIDs or sender addresses; consult the vendor advisory at https://downloads.seppmail.com/extrelnotes/150/ERN15.0.html#seppmail-vulnerability-disclosure-1503 for detailed upgrade and validation procedures. No workarounds are documented; patching is the primary mitigation.
Remote code execution in SeppMail secure email gateway versions 15.0.2.1 and earlier allows unauthenticated attackers to
Command injection in SEPPmail Secure Email Gateway before 15.0.1 via PDF encryption password.
SEPPmail Secure Email Gateway before version 15.0.3 allows attackers to bypass subject sanitization and forge security t
SEPPmail Secure Email Gateway before version 15.0.3 fails to properly authenticate inner messages within S/MIME-encrypte
Account takeover in SEPPmail Secure Email Gateway versions before 15.0.3 allows unauthenticated attackers to reset victi
SEPPmail Secure Email Gateway before version 15.0.3 allows remote attackers to bypass subject line sanitization controls
SEPPmail Secure Email Gateway before version 15.0.3 allows remote attackers to inject malicious certificates into S/MIME
SEPPmail Secure Email Gateway versions before 15.0.1 fail to properly validate S/MIME message headers, enabling attacker
Improper filename validation in SEPPmail Secure Email Gateway's GINA web interface (versions before 15.0.1) enables unau
SEPPmail Secure Email Gateway versions prior to 15.0.1 fail to properly isolate decrypted PGP message content from surro
SEPPmail Secure Email Gateway versions before 15.0.1 misinterpret email addresses in message headers, enabling attackers
Session hijacking in SEPPmail Secure Email Gateway and SEPPmail Cloud before 15.0.4.2 lets an attacker who can observe t
Same weakness CWE-20 – Improper Input Validation
View allSame technique Information Disclosure
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External POC / Exploit Code
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