CVE-2026-2746Network attack vector

Email forgery via missing PGP signature tag

Published Mar 4, 2026 · Updated Mar 4, 2026

Improper PGP signature verification in SEPPmail Secure Email Gateway before 15.0.1 allows remote attackers to pass forged emails as authentic. The PGP processing path omits the signature-status tag that should carry verification failure to the recipient, suppressing the visible authenticity warning. Network access is sufficient and requires no account or recipient interaction; SEPPmail has not identified the internal function, and impact is limited to email-origin integrity.

CVSS severity6.9
Medium
EPSS probability0.16%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper PGP signature verification in SEPPmail Secure Email Gateway before 15.0.1 allows remote attackers to pass forged emails as authentic. The PGP processing path omits the signature-status tag that should carry verification failure to the recipient, suppressing the visible authenticity warning. Network access is sufficient and requires no account or recipient interaction; SEPPmail has not identified the internal function, and impact is limited to email-origin integrity.

The record

CVE
CVE-2026-2746
Published
Mar 4, 2026
Updated
Mar 4, 2026
Vendor
SEPPmail
Product
Secure Email Gateway
Classifications
CWE-347, CAPEC-194
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 4, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 4, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <15.0.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

SEPPmail · Secure Email Gatewayversion=0 <15.0.1

Published CVSS scores

5.3NIST National Vulnerability DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
6.9Switzerland Government Common Vulnerability ProgramCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-347Improper Verification of Cryptographic Signature
CAPEC-194Fake the Source of Data

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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