This firmware is only for versions 4.1 of the Cisco Linksys BEFSR41 EtherFast Cable/DSL Router with 4-Port Switch
2.00.4 build 5 1. Fixed an issue with PPTP mode configuration with the Setup wizard.
2. Fixed UPnP test failed.
3. Fixed RIP not updating the router table.
4. Fixed Dynamic Route not working properly
5. Fixed static Router configuration failure
6. Fixed maximum static route.
7. Fixed where client can't get IP after adding a static route.
8. Fixed UPnP link speed/duration and send/receive packet status
in the Internet Gateway.
9. Fixed clne PC's MAC address is accessable remotely.
10. Fixed QoS application based accepting invalid entry.
11. Fixed IGMPv2 client leave silently after 100 seconds.
Here's other similar drivers that are different versions or releases for different operating systems: