CVE-2026-42392Network attack vector

Process-memory disclosure via invalid IMAP URLFETCH

Published Aug 28, 2026 · Updated Aug 28, 2026

Information disclosure in OX Dovecot CE before 2.4.5 and OX Dovecot Pro before 3.1.6 allows remote authenticated users to read process memory. The IMAP URLFETCH error path copies uninitialized memory into the client-visible response when it processes an invalid command. Valid IMAP credentials and enabled URLAUTH functionality are required; the returned memory can contain sensitive process data.

CVSS severity4.3
Medium
EPSS probability0.23%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in OX Dovecot CE before 2.4.5 and OX Dovecot Pro before 3.1.6 allows remote authenticated users to read process memory. The IMAP URLFETCH error path copies uninitialized memory into the client-visible response when it processes an invalid command. Valid IMAP credentials and enabled URLAUTH functionality are required; the returned memory can contain sensitive process data.

The record

CVE
CVE-2026-42392
Published
Aug 28, 2026
Updated
Aug 28, 2026
Vendor
Open-Xchange GmbH
Product
OX Dovecot CE
Classifications
CWE-200, T1005
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 28, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 28, 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=2.3.0 <2.4.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Open-Xchange GmbH · OX Dovecot CEversion=2.3.0 <2.4.5
Open-Xchange GmbH · OX Dovecot Proversion=2.3.0 <3.1.6

Published CVSS scores

4.3Open-XchangeCVSS:3.1/AV:N/AC:L/PR:L/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
T1005Data from Local System

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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