A patch update is a software and operating system, or OS, update that addresses security vulnerabilities within a program or product.
Now we'll discuss patch updates provided to the company by the OS software vendor.
With patch updates, the OS should be upgraded to its latest software version.
Sometimes patches are released to fix a security vulnerability in the software.
As soon as OS vendors publish a patch and the vulnerability fix, malicious actors know exactly where the vulnerability is in systems
running the out-of-date OS.
This is why it's important for organizations to run patch updates as soon as they are released.
For example, my team had to perform an emergency patch to address a recent vulnerability found in a commonly used programming library.
The library is used almost everywhere, so we had to quickly patch most of our servers and applications to fix the vulnerability.
The newly updated OS should be added to the baseline configuration, also called the baseline image.
A baseline configuration is a documented set of specifications within a system that is used as a basis for future builds,
releases, and updates.
For example, a baseline may contain a firewall rule with a list of allowed and disallowed network ports. If a security team suspects
unusual activity affecting the OS, they can compare the current configuration to the baseline and make sure that nothing has been changed.