Open-Xchange Dovecot Pro/Dovecot CE Message Parsing memory allocation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.4$0-$5k1.84-

Summaryinfo

A vulnerability, which was classified as problematic, was found in Open-Xchange Dovecot Pro and Dovecot CE. This issue affects some unknown processing of the component Message Parsing. Executing a manipulation can lead to memory allocation. The identification of this vulnerability is CVE-2026-27852. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in Open-Xchange Dovecot Pro and Dovecot CE (affected version not known). It has been declared as problematic. This vulnerability affects some unknown functionality of the component Message Parsing. The manipulation with an unknown input leads to a memory allocation vulnerability. The CWE definition for the vulnerability is CWE-789. The product allocates memory based on an untrusted, large size value, but it does not ensure that the size is within expected limits, allowing arbitrary amounts of memory to be allocated. As an impact it is known to affect availability. CVE summarizes:

An attacker that can send mail to a user can craft a message whose headers contain a very large number of email addresses or MIME parameters, which causes excessive memory usage when the message is later parsed. The message is still delivered, but reading it over IMAP can exhaust the memory limit of the process and terminate it, causing denial of service for the affected user. Update to non-vulnerable version. No publicly available exploits are known.

The advisory is shared for download at documentation.open-xchange.com. This vulnerability was named CVE-2026-27852 since 02/24/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-3076). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Open Source Dovecot

Productinfo

Type

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.4

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

CNA Base Score: 7.5
CNA Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Memory allocation
CWE: CWE-789 / CWE-400 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

02/24/2026 CVE reserved
08/28/2026 +184 days Advisory disclosed
08/28/2026 +0 days VulDB entry created
08/28/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: open-xchange.com

Advisory: documentation.open-xchange.com
Status: Not defined

CVE: CVE-2026-27852 (🔒)
GCVE (CVE): GCVE-0-2026-27852
GCVE (VulDB): GCVE-100-396664
CERT Bund: WID-SEC-2026-3076 - Dovecot: Mehrere Schwachstellen

Entryinfo

Created: 08/28/2026 13:40
Updated: 08/28/2026 14:37
Changes: 08/28/2026 13:40 (61), 08/28/2026 14:37 (7)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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