CVE-2026-27852

Summary

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.

Affected Software

VendorProductVersion RangeStatus
Open-Xchange GmbHOX Dovecot Pro2.3.0 < 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 CE2.3.0 < 2.4.5affected

Weaknesses

  • CWE-400: Uncontrolled Resource Consumption

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: yes
    • Technical Impact: partial

References