iCloud will not let me upload with this MacBook Safari Version 5.1.10 (6534.59.10). There are no other updates for this version I'm aware of. What is the next Safari upgrade?

iCloud will not let me upload with this Safari Version 5.1.10 (6534.59.10). There are no other updates for this version according to Software Update function. What is the next Safari upgrade?

Model Name: MacBook

Model Identifier: MacBook4,1

Processor Name: Intel Core 2 Duo

Processor Speed: 2.4 GHz

Number Of Processors: 1

Total Number Of Cores: 2

L2 Cache: 3 MB

Memory: 2 GB

Bus Speed: 800 MHz

Boot ROM Version: MB41.00C1.B00

SMC Version (system): 1.31f1

Serial Number (system): W8813L410P1

Hardware UUID: 17531E1C-3F86-5CE4-B8F5-9AD210669CFA

Sudden Motion Sensor:

State: Enabled