CVE-2026-52687

Summary

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.

Affected Software

VendorProductVersion RangeStatus
Open-Xchange GmbHOX Dovecot Pro2.3.11 < 2.3.22.2affected
Open-Xchange GmbHOX Dovecot Pro3.0.0 < 3.0.7affected
Open-Xchange GmbHOX Dovecot Pro3.1.0 < 3.1.6affected
Open-Xchange GmbHOX Dovecot CE2.3.11 < 2.4.5affected

Weaknesses

  • CWE-400: Uncontrolled Resource Consumption

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References