Defining a short log retention duration can reduce an organization’s ability to backtrace the actions of malicious actors in case of a security incident.

Logging allows operational and security teams to get detailed and real-time feedback on an information system’s events. The logging coverage enables them to quickly react to events, ranging from the most benign bugs to the most impactful security incidents, such as intrusions.

Apart from security detection, logging capabilities also directly influence future digital forensic analyses. For example, detailed logging will allow investigators to establish a timeline of the actions perpetrated by an attacker.

Ask Yourself Whether

• This component is essential for the information system infrastructure.
• This component is essential for mission-critical functions.
• Compliance policies require traceability for a longer duration.

There is a risk if you answered yes to any of those questions.

Recommended Secure Coding Practices

Setting log retention period to 14 days is the bare minimum. It’s recommended to increase it to 30 days or above.

Sensitive Code Example

For AWS Cloudwatch Logs:

resource "aws_cloudwatch_log_group" "example" {
  name = "example"
  retention_in_days = 3 # Sensitive
}

For Azure Firewall Policy:

resource "azurerm_firewall_policy" "example" {
  insights {
    enabled = true
    retention_in_days = 7 # Sensitive
  }
}

For Google Cloud Logging buckets:

resource "google_logging_project_bucket_config" "example" {
    project = var.project
    location = "global"
    retention_days = 7 # Sensitive
    bucket_id = "_Default"
}

Compliant Solution

For AWS Cloudwatch Logs:

resource "aws_cloudwatch_log_group" "example" {
  name = "example"
  retention_in_days = 30
}

For Azure Firewall Policy:

resource "azurerm_firewall_policy" "example" {
  insights {
    enabled = true
    retention_in_days = 30
  }
}

For Google Cloud Logging buckets:

resource "google_logging_project_bucket_config" "example" {
    project = var.project
    location = "global"
    retention_days = 30
    bucket_id = "_Default"
}