CVE-2026-27852
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.
Published:Aug 28, 2026
Last Modified:Sep 1, 2026
EPS:Aug 28, 2026
EPSS Score:0.00359
CVSS Score:7.5
Affected Products
Vendor
Product
Action
Vendor
Open-xchange
Product
Ox Dovecot Ce
Open-xchange
Ox Dovecot Ce
Vendor
Open-xchange
Product
Ox Dovecot Pro
Open-xchange
Ox Dovecot Pro
Exploits
No exploit reference
Common Weakness Enumeration
Common Attack Pattern Enumeration and Classification (CAPEC)
Related CVEs
Common Vulnerability Scoring System
Attack Vector
Network
Adjacent
Local
Physical
Privileges Required
None
Low
High
User Interaction
None
Required
Scope
Unchanged
Changed
Confidentiality
None
Low
High
Integrity
None
Low
High
Availability
None
Low
High
