CVE-2026-52687

An attacker that has valid credentials can select a compression algorithm for the IMAP connection whose decompression state requires a large amount of memory, and open several such connections. The memory limit of the process is reached with only a few connections, terminating the process and all connections it handles, which can cause degradation or denial of service for IMAP. Disable IMAP compression. Alternatively limit the number of connections handled by a single imap-login process, though this has a performance impact. Update to non-vulnerable version. No publicly available exploits are known.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0003.json

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-28 12:16

Updated : 2026-09-03 18:13

NVD link : CVE-2026-52687

Mitre link : CVE-2026-52687

CVE.ORG link : CVE-2026-52687

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

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