Security logs explained: What they are and why they matter

In any modern business venture using technology, security must be top of mind. Securing and monitoring all your IT assets and their performance helps ensure your systems and information are safe, your products and applications are functioning properly, and your customers are happy. This becomes more difficult and more complicated as the world of technology constantly expands and evolves, and security threats become more complex.

To face these threats, it’s important to know your systems and know the tools and methods available to help you effectively monitor those systems so that you’re alerted to unusual events, respond quickly to security incidents, and can prevent their recurrence in the future. Security logs can help you do this.

Security logs—also known as security event logs—are digital records of system activities and events, such as login attempts, policy changes, and access to sensitive data. These logs are accrued from a variety of sources like databases, servers, workstations, and firewalls, and provide a timeline of what’s happening in the system.

This timeline is essential to identifying and troubleshooting unusual activity and potential threats like access attempts that can lead to breaches. With the record these logs provide, security teams can then learn what was attempted or accessed, shore up weaknesses, and prevent recurrences.

Security logs can originate from a wide range of sources, each offering unique insights into system activities and potential threats.

Security logs can come from many sources:

• Cloud logs: Track activities within a cloud environment, noting activities and events like data transfers, user activity, and network traffic between cloud instances.
• Event logs: Track significant occurrences, including both failed and successful login attempts.
• Server logs: Record activities on servers, crucial for identifying performance issues and attacks.
• Endpoint logs: Focus on activities from devices like laptops and mobile phones to monitor for vulnerabilities.
• Proxy logs: Track web traffic to detect abnormal behavior.
• IoT logs: Collect and record data from connected devices to ensure hardware and software security throughout the network.

Security logs bring multiple benefits, such as:

Early threat detection

The enhanced visibility that these logs provide makes it easier for your security team to monitor systems proactively, identifying and fixing vulnerabilities before an issue can occur.

Incident response

Using security log data, IT teams can identify suspicious activity early and act quickly, before a breach escalates. The real-time information they supply means that unusual activity can be monitored for and acted upon quickly, limiting the damage of the incident or even preventing it altogether.

Forensic analysis

Forensic analysis of a security incident is crucial for learning how access was gained and preventing a recurrence. Security logs provide a timeline of events, allowing investigators to trace back to find the origin of a breach and discover the extent of its impact.

Compliance and legal requirements

The information provided by logs are essential for meeting compliance standards like GDPR and HIPAA, ensuring proper record-keeping and monitoring.

While the format depends on the source, common elements of security logs include the following:

Logs contain a lot of information from a variety of sources. To use this information effectively, it’s important to set up tools and processes to help manage them in a meaningful, useful, and efficient way. Here are a few recommended methods.

Log aggregation

Log aggregation is the process of collecting, organizing, and storing logs from multiple sources in one centralized location. From this repository, you’re better able to understand and use the collected security data because you have a more comprehensive view of it.

This process is usually performed using a solution like a Security Information and Event Management (SIEM) system. The SIEM system ingests the information gathered from security logs, parses it for events and anomalies, and then generates a report alerting you to those events and anomalies for further investigation.

Automated anomaly detection

Anomaly detection is the process of identifying unusual or potentially dangerous activity within your security logs. Once your logs are aggregated into a centralized location, it’s important to monitor them for any events or incidents that are outside normal daily activity as anomalies could indicate unauthorized attempts at access. Data management systems can be used to detect anomalies automatically and alert security teams at the first sign of unusual activity.

Maintaining log integrity

The importance of security logs to security processes and to staying compliant with regulations within your realm of business means that the integrity of your logs is critical. For this reason, it’s imperative to put protocols in place to protect against unauthorized activity within your logs and to secure the information that the logs contain. Some best practices include:

• Using secure storage and backup systems
• Recording logs in two locations, locally and on a remote server, with users given access to one but not both – this allows the two logs to be compared for anomaly detection purposes
• Using write-once media to record log data, to prevent data being overwritten (by a hacker hoping to hide their access, for instance.
• Performing regular log audits

Log routing

Security log data storage can feel overwhelming due to the soaring log growth we see today and the associated cost of storing them. For this reason, consider routing logs to object storage (S3, Azure Blob) to support long-term data retention without going over budget.

Object storage is a method of storage where data is organized into discrete units called “objects”, containing their own data, metadata, and identifier. This allows them to be stored without the bulk of a hierarchy of folders or directories.

Managing security logs can be daunting without the right tools, which is why organizations rely on SIEM systems to centralize, analyze, and correlate logs from diverse sources in real-time. Some important features to consider when choosing a tool include:

• Scalability: The ability to expand and grow with your log data as needed means less headache down the road.
• Real-time monitoring: Alerts you to potential data threats as unusual activity occurs.
• Integration capabilities: Built-in integrations can help with things like log aggregation and log reduction, which filters out redundant or irrelevant log entries.

A tool that integrates these features into one platform is ideal, allowing for streamlined log management with centralized visibility. A centralized and integrated platform puts your security log information in one place, giving you maximum visibility and responsiveness.

Security logs provide a broad range of benefits to enterprises, recording activity taking place within systems and applications and making it possible to improve their performance and security exponentially over time.

By monitoring these logs, security teams can more readily detect and respond to potential threats, stopping the loss of valuable information. And by analyzing the information contained in security logs, an incident can be tracked back to its origin, making it possible to identify patterns and anomalies that can then be tracked with alerts set to notify you should they occur in the future.

Implementing a comprehensive logging strategy means an improved cybersecurity posture for your enterprise and more confidence and peace of mind for you and your customers.

What is the importance of security logs?

The enhanced visibility that logs provide makes it easier for your security team to monitor systems proactively, identifying and fixing vulnerabilities before an issue can occur.

What do security logs track?

Security logs can track specific events and activities within systems, depending on legal requirements or needs specific to a particular industry. Some examples of important events to track are login attempts, errors, changes to settings, devices attached or detached, firewall alerts, and potential breaches.

What are common elements of security logs?

Timestamp, Event ID, Source, User information, and Event type