CVE-2015-3420

Publication date 19 September 2017

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

The ssl-proxy-openssl.c function in Dovecot before 2.2.17, when SSLv3 is disabled, allow remote attackers to cause a denial of service (login process crash) via vectors related to handshake failures.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
dovecot	15.04 vivid	Not affected
	14.10 utopic	Not affected
	14.04 LTS trusty	Not affected
	12.04 LTS precise	Not affected
	10.04 LTS lucid	Not affected

Notes

tyhicks

Thanks to Hanno's analysis on the dovecot list, I believe that the issue was introduced by http://hg.dovecot.org/dovecot-2.2/rev/09d3c9c6f0ad. That commit was first released in 2.2.14.

Severity score breakdown

CVSS version: CVSS v3.0

Base score 5.9 · Medium

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	High
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality impact	None
Integrity impact	None
Availability impact	High

Scores

Parameter	Value
Base score	5.9 · Medium
Exploitability score	-
Impact score	-

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H