| Date | IP Address |
| 2024-11-07 | 89.191.67.180 (ClassC) |
| 2024-12-27 | 89.191.86.209 (ClassC) |
| 2025-01-25 | 89.191.91.171 (ClassC) |
| Date | Domain | IP |
| pbe.urlaub.check24.at | 2024-09-30 | 89.191.86.207 |
| staging.urlaub.check24.at | 2025-01-19 | 89.191.67.180 |
| m.urlaub.check24.at | 2024-04-09 | 89.191.67.180 |
| integration.urlaub.check24.at | 2024-11-24 | 89.191.67.180 |
| assistant.urlaub.check24.at | 2024-12-19 | 89.191.86.207 |