OpenSMTPD Remote Code Execution Vulnerability (CVE-2020-8794) Threat Alert

OpenSMTPD Remote Code Execution Vulnerability (CVE-2020-8794) Threat Alert

March 18, 2020 | Mina Hao

Overview

On February 24, local time, researchers from Qualys released a remote code execution vulnerability (CVE-2020-8794) existing in OpenSMTPD.

As part of the OpenBSD part, OpenSMTPD (also known as OpenBSD’s mail server) is a free implementation of the server-side SMTP protocol as defined by RFC 5321.

CVE-2020-8794 is an out-of-bounds read vulnerability. Attackers could exploit this vulnerability to inject arbitrary commands into the envelope file that are then executed as root.

According to researchers, they developed a simple exploit for this vulnerability and successfully tested it against OpenBSD 6.6, OpenBSD 5.9, Debian 10 (stable), Debian 11 (testing), and Fedora 31.

Reference:

https://www.openwall.com/lists/oss-security/2020/02/24/5

Affected Versions

  • OpenSMTPD < 6.6.4p1

Unaffected Versions

  • OpenSMTPD = 6.6.4p1

Solution

OpenBSD has released new versions to fix the preceding vulnerability. Affected users are advised to upgrade as soon as possible.

Download link:

https://github.com/OpenSMTPD/OpenSMTPD/releases

Statement

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