USN-4875-1: OpenSMTPD vulnerabilities
15 March 2021
Several security issues were fixed in OpenSMTPD.
Releases
Packages
- opensmtpd - secure, reliable, lean, and easy-to configure SMTP server
Details
It was discovered that OpenSMTPD incorrectly verified the sender's or
receiver's e-mail addresses under certain conditions. An attacker could
possibly use this vulnerability to execute arbitrary commands as root.
(CVE-2020-7247)
It was discovered that OpenSMTPD did not properly handle hardlinks under
certain conditions. An unprivileged local attacker could possibly use this
issue to obtain sensitive information. This issue only affected Ubuntu
16.04 ESM. (CVE-2020-8793)
It was discovered that OpenSMTPD mishandled certain input. A remote,
unauthenticated attacker could possibly use this vulnerability to execute
arbitrary shell commands as any non-root user. This issue only affected
Ubuntu 16.04 ESM. (CVE-2020-8794)
Update instructions
The problem can be corrected by updating your system to the following package versions:
Ubuntu 16.04
-
opensmtpd
-
5.7.3p2-1ubuntu0.1~esm2
Available with Ubuntu Pro
Ubuntu 14.04
-
opensmtpd
-
5.4.1p1-1ubuntu0.1~esm1
Available with Ubuntu Pro
In general, a standard system update will make all the necessary changes.