Open-Xchange OX Dovecot Pro up to 2.4.0/3.1.0 improper authentication

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.2$0-$5k0.19

Summaryinfo

A vulnerability labeled as critical has been found in Open-Xchange OX Dovecot Pro up to 2.4.0/3.1.0. This impacts an unknown function. Such manipulation leads to improper authentication. This vulnerability is documented as CVE-2025-59028. The attack can be executed remotely. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Open-Xchange OX Dovecot Pro up to 2.4.0/3.1.0. Affected by this issue is an unknown part. The manipulation with an unknown input leads to a improper authentication vulnerability. Using CWE to declare the problem leads to CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. Impacted is availability. CVE summarizes:

When sending invalid base64 SASL data, login process is disconnected from the auth server, causing all active authentication sessions to fail. Invalid BASE64 data can be used to DoS a vulnerable server to break concurrent logins. Install fixed version or disable concurrency in login processes (heavy perfomance penalty on large deployments). No publicly available exploits are known.

The advisory is available at documentation.open-xchange.com. This vulnerability is handled as CVE-2025-59028 since 09/08/2025. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. The technical details are unknown and an exploit is not available.

The vulnerability scanner Nessus provides a plugin with the ID 304143 (Linux Distros Unpatched Vulnerability : CVE-2025-59028), which helps to determine the existence of the flaw in a target environment.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (304143) and CERT Bund (WID-SEC-2026-0891). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

  • Open Source Dovecot

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.2

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.3
CNA Vector: 🔒

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper authentication
CWE: CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 304143
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-59028

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Timelineinfo

09/08/2025 CVE reserved
03/27/2026 +200 days Advisory disclosed
03/27/2026 +0 days VulDB entry created
03/28/2026 +1 days VulDB entry last update

Sourcesinfo

Vendor: open-xchange.com

Advisory: adv-2026-0001
Status: Confirmed

CVE: CVE-2025-59028 (🔒)
GCVE (CVE): GCVE-0-2025-59028
GCVE (VulDB): GCVE-100-353846
CERT Bund: WID-SEC-2026-0891 - Dovecot: Mehrere Schwachstellen

Entryinfo

Created: 03/27/2026 09:51
Updated: 03/28/2026 14:35
Changes: 03/27/2026 09:51 (63), 03/28/2026 01:25 (7), 03/28/2026 14:35 (2)
Complete: 🔍
Cache ID: 216:9B2:103

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