modify kernel to accept listen <1023 not uid=0 ?

Ed df at bsd.it
Sat Jul 31 00:44:40 PDT 2004


On Saturday 31 July 2004 09:27, rmkml wrote:
> BSD not accept listen <1023


Bad idea !


This will permit to _any_ user on your box to simulate that service.

Example:

1) john.doe@ logs in

2) he crash your POP3 daemon (port 110)

3) he launch his own POP3 daemon that will sniff every user/pwd

Same thing could happen for every daemon that doesn't need root privileges to 
bind that port. However, if you use a packet filter you could avoid this 
using the user/group keyword for every service.


	Ed






More information about the Kernel mailing list