CVE-2020-28019

Publication date 4 May 2021

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

Exim 4 before 4.94.2 has Improper Initialization that can lead to recursion-based stack consumption or other consequences. This occurs because use of certain getc functions is mishandled when a client uses BDAT instead of DATA.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
exim4	22.04 LTS jammy	Fixed 4.94-15ubuntu1.2
	21.10 impish	Fixed 4.94-15ubuntu1.2
	21.04 hirsute	Fixed 4.94-15ubuntu1.2
	20.10 groovy	Fixed 4.94-7ubuntu1.2
	20.04 LTS focal	Fixed 4.93-13ubuntu1.5
	18.04 LTS bionic	Fixed 4.90.1-1ubuntu1.8
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not affected

Notes

leosilva

trusty/xenial ESM not affected. vulnerability was introduced by: https://git.exim.org/exim.git/patch/7e3ce68e68ab9b8906a637d352993abf361554e2

Severity score breakdown

Parameter	Value
Base score	7.5 · High
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	High
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H