CVE-2018-6789

Publication date 7 February 2018

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

An issue was discovered in the base64d function in the SMTP listener in Exim before 4.90.1. By sending a handcrafted message, a buffer overflow may happen. This can be used to execute code remotely.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
exim4	17.10 artful	Fixed 4.89-5ubuntu1.3
	16.04 LTS xenial	Fixed 4.86.2-2ubuntu2.3
	14.04 LTS trusty	Fixed 4.82-3ubuntu2.4

Severity score breakdown

CVSS version: CVSS v3.0

Base score 9.8 · Critical

Base metrics

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

Scores

Parameter	Value
Base score	9.8 · Critical
Exploitability score	-
Impact score	-

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

Related Ubuntu Security Notices (USN)

USN-3565-1
Exim vulnerability
12 February 2018