I really dont think you can patch the crack around the hole the pipe goes through. If there is a leak it has to be found and fixed. Blocking the hole where its coming out of isnt preventing the area that needs to be fixed and will most likely start coming out of somewhere else.
Originally Posted by miscione
I have a leak where the waste pipe goes through the foundation. Can this be fix from inside the house or do i need to dig up the outside and reseal the pipe?
If there is an annular space around the pipe (between the foundation wall and the pipe), the space can be packed with hydraulic cement. It is a non-shrink product designed for water-stopping, and is often used in this application. It will harden in wet conditions as well.
You buy it in small tubs and mix it to a peanut butter consistency. Use a small putty knife to pack as much of it as you can in the annulus.
And yes, do it from the inside.
As mentioned, water will probably find another way in if your foundation is cracked.