CVE-2026-0394Network attack vector

Pre-auth password disclosure via domain path traversal

Published Mar 27, 2026 · Updated Mar 27, 2026

Path traversal in Open-Xchange Dovecot Pro 2.3.0 and earlier allows remote attackers to read password files during authentication. The passwd-file passdb expands attacker-controlled %d domain text into a per-domain file path without containing directory-partial traversal, allowing the lookup to escape its base and open /etc/passwd. Exposure requires per-domain passwd files one path component above /etc, or a slash in allowed username characters; leaked passwords enable wrongful login, while userdb lookups can admit system users.

CVSS severity5.3
Medium
EPSS probability0.43%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Path traversal in Open-Xchange Dovecot Pro 2.3.0 and earlier allows remote attackers to read password files during authentication. The passwd-file passdb expands attacker-controlled %d domain text into a per-domain file path without containing directory-partial traversal, allowing the lookup to escape its base and open /etc/passwd. Exposure requires per-domain passwd files one path component above /etc, or a slash in allowed username characters; leaked passwords enable wrongful login, while userdb lookups can admit system users.

The record

CVE
CVE-2026-0394
Published
Mar 27, 2026
Updated
Mar 27, 2026
Vendor
Open-Xchange GmbH
Product
Dovecot Pro
Classifications
CWE-22, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 27, 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 <=2.3.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Open-Xchange GmbH · Dovecot Proversion=0 <=2.3.0

Published CVSS scores

5.3Open-XchangeCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A: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.

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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-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
T1190Exploit Public-Facing Application

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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