Open-Xchange Security Advisory 2020-02-12

Affected product: Dovecot Core Internal reference: DOV-3744 (JIRA ID) Vulnerability type: Improper Input Validation (CWE-30) Vulnerable version: 2.3.9 Vulnerable component: submission-login, lmtp Fixed version: 2.3.9.3 Report confidence: Confirmed Solution status: Fixed Researcher credits: Open-Xchange oy Vendor notification: 2020-01-14 CVE reference: CVE-2020-7046 CVSS: 7.5 (CVSS3.1:AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

Vulnerability Details:

lib-smtp doesn't handle truncated command parameters properly, resulting in infinite loop taking 100% CPU for the process. This happens for LMTP (where it doesn't matter so much) and also for submission-login where unauthenticated users can trigger it.

Risk:

Attacker can cause submission-login and lmtp processes to be exhausted, leading into denial of service and CPU resource exhaustion.

Solution:

Upgrade to 2.3.9.3.