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SeppmailApplication

CVE-2026-27444

HIGH · 7.5 CVSS v3.1 Published 2026-03-04
Fix available
A fix is available. Upgrade to 15.0.1 or later.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
SEPPmail Secure Email Gateway before version 15.0.1 incorrectly interprets email addresses in the email headers, causing an interpretation conflict with other mail infrastructure that allows an attacker to fake the source of the email or decrypt it.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

SEPPmail Secure Email Gateway before version 15.0.1 has a header interpretation flaw where it incorrectly parses email addresses from email headers, creating conflicts with downstream mail infrastructure. This allows attackers to spoof the email source or potentially decrypt encrypted messages by manipulating header fields.

MitigationUpgrade SEPPmail Secure Email Gateway to version 15.0.1 or later. Review email header processing configurations and audit logs for signs of header manipulation or anomalous email routing.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
SeppmailApplication
Affected:< 15.0.1

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify SEPPmail installation version
    Use the system's package manager or check the SEPPmail administrative interface for the currently installed version number. Consult SEPPmail documentation for version lookup commands if available.
    Affected if The installed version is any release before 15.0.1 (e.g., 14.x.x, 13.x.x, etc.)
  2. Confirm email gateway processing is active
    Verify that the SEPPmail gateway is actively processing, receiving, or relaying email messages. Check service status and email queue.
    Affected if The gateway is operational and processing email traffic, as the vulnerability lies in how email headers are parsed during normal operation
  3. Inspect email header parsing configuration
    Review the SEPPmail configuration settings related to header processing, email address extraction, and header-based routing rules.
    Affected if Header parsing or email address extraction from headers is enabled in the configuration
  4. Audit email routing for anomalies
    Examine email logs and routing tables for signs of unusual header manipulation, unexpected source addresses, or anomalous email routing patterns.
    Affected if Logs show unexpected email sources, header inconsistencies, or routing conflicts with downstream mail infrastructure

Your environment is affected if the installed SEPPmail version is below 15.0.1 and the email gateway is actively processing messages with header-based parsing enabled.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 15.0.1 or later
Fixed in 15.0.1
Interim mitigation

Upgrade SEPPmail Secure Email Gateway to version 15.0.1 or later. Review email header processing configurations and audit logs for signs of header manipulation or anomalous email routing.

Recommended fix Moderate confidence

SEPPmail Secure Email Gateway 15.0.1

  1. 1. Backup the current SEPPmail configuration and email data before proceeding with any changes.
  2. 2. Download SEPPmail Secure Email Gateway version 15.0.1 or later from the official source at downloads.seppmail.com.
  3. 3. Review the upgrade documentation provided with version 15.0.1 for any specific migration requirements.
  4. 4. Perform the upgrade following the vendor's documented upgrade procedure.
  5. 5. After upgrading, verify that email header interpretation is working correctly by testing email flows.
  6. 6. Confirm that the version has been successfully updated by checking the SEPPmail admin interface or command line.
Caveat Review vendor release notes for version 15.0.1 for any configuration or feature changes that may affect existing setup

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Seppmail Scoped from the published advisory
  • Consultation4.0 h
  • Implementation3.0 h
  • Testing6.0 h
  • Review / QA3.0 h
16.0 hours of engineering $2,780
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,448.

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-27444 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data