Controls/EDCA-RES-004.json

{
  "id": "EDCA-RES-004",
  "title": "Mailbox database deleted item retention is at least 14 days",
  "description": "The Recoverable Items folder (also known as the dumpster) is the hidden mailbox folder where deleted items are staged after removal from the Deleted Items folder, providing a recovery window before permanent purge. The DeletedItemRetention on each mailbox database controls how long deleted items are retained in the dumpster before permanent removal. DeletedItemRetention MUST be set to a minimum of 14 days so that accidentally deleted items can be recovered without requiring a backup restore.",
  "verify": true,
  "subject": "Database",
  "category": "Resilience",
  "severity": "Medium",
  "severityWeight": 5,
  "frameworks": [
    "Best Practice",
    "CIS"
  ],
  "references": [
    {
      "name": "CIS 2.1.2 (L1): Ensure Keep deleted items for the specified number of days is set to 14",
      "url": "https://www.cisecurity.org/benchmark/microsoft_exchange_server"
    },
    {
      "name": "Configure deleted item retention and recoverable items quotas",
      "url": "https://learn.microsoft.com/en-us/exchange/recipients/mailbox-databases/configure-deleted-item-retention-and-recoverable-items-quotas"
    }
  ],
  "remediation": {
    "automatable": true,
    "description": "Set DeletedItemRetention to at least 14 days on every mailbox database.",
    "scriptTemplate": "# Set deleted item retention to 14 days on a specific mailbox database.\n# To target a specific database: replace 'DatabaseName' with the actual database name.\nSet-MailboxDatabase -Identity 'DatabaseName' -DeletedItemRetention 14.00:00:00"
  },
  "considerations": "Increasing the retention period will consume additional storage in the Recoverable Items folder. Review mailbox database storage capacity before extending the retention period significantly beyond the recommended minimum.",
  "roles": [
    "Mailbox"
  ]
}