How to solve
Most software will sooner or later encounter a software error. These so-called bugs can make software unstable, or work differently than the programmer had intended. Some of these bugs turn out to be security related, like errors which don't properly check the input, or the amount of data stored in a temporary buffer. This is a weakness, which makes the software vulnerable for abuse.
Most Linux distributions, like Debian and Ubuntu, mark which package updates are security related. It is then the task for the system administrator to discover these as quickly as possible, and implement them. Depending on company size this can be done as an ad-hoc activity, or using a predefined software patch management process.
Lynis tests for the presence of any vulnerable packages. When it finds any, this control is triggered, with a related warning. It is marked as high impact, as each vulnerable package has a different potential for being exploited by attackers. Still you should determine the impact for your environment, and see when you want to apply the related security update.
- apt-get update
- apt-get upgrade
Consider using a tool like unattended-upgrade to keep the time of window for vulnerable packages as low as possible. It can be configured to automatically install security updates, while leaving normal updates for later moment of deployment.
Need more details?
Consider the upgrade to Lynis Enterprise to receive additional details and guidance. The Enterprise version helps to you with daily health checks of your environment, learn in-depth system hardening, and resources to protect your systems better.See demo
Lynis is a technical security auditing tool for Unix flavors like Linux, macOS, AIX, Solaris, and *BSD. It is open source software and free to use. Typical usage include system hardening, compliance testing, and vulnerability scanning. The project has an active community, including development via GitHub.
Do you need to collect data from multiple systems or compliance reporting? Lynis Enterprise uses Lynis to collect the data and make your work easier.
Benefits: automate security audits, detailed reporting, compliance testing.
- Centralized management
- Improvement plan with priorities
- Predefined policies
- Integration (API)
- Improvement snippets for tools like Ansible, Chef, Cfengine, Puppet, and SaltStack