Arch Linux: ASA-201910-1 Critical: Exim Arbitrary Code Execution

Arch Linux Security Advisory ASA-201910-1
========================================
Severity: Critical
Date    : 2019-10-02
CVE-ID  : CVE-2019-16928
Package : exim
Type    : arbitrary code execution
Remote  : Yes
Link    : https://security.archlinux.org/AVG-1038

Summary
======
The package exim before version 4.92.3-1 is vulnerable to arbitrary
code execution.

Resolution
=========
Upgrade to 4.92.3-1.

# pacman -Syu "exim>=4.92.3-1"

The problem has been fixed upstream in version 4.92.3.

Workaround
=========
None.

Description
==========
It has been discovered that Exim before 4.92.3 is vulnerable to a heap-based buffer overflow in string_vformat (string.c) involving a long
EHLO command leading to remote code execution.

Impact
=====
A remote attacker is able to execute arbitrary code on the affected
host by sending a specifically crafted long EHLO command.

References
=========
https://www.exim.org/static/doc/security/CVE-2019-16928.txt
https://bugs.exim.org/show_bug.cgi?id=2449

https://www.openwall.com/lists/oss-security/2019/09/28/1
https://security.archlinux.org/CVE-2019-16928