Most SVG fonts are made up of PNG images, so in order to edit them, you need to treat them as such.
To change the colors of an SVG font within Photoshop, you can right click on the text layer, select blending options, and use the color overlay option.
To change the colors of an SVG font within Illustrator, it's a little more fiddly, but follow these steps;
- Create a layer just below the text layer
- Choose the rectangle tool and set it to whatever color you want to change the text to.
- Draw a rectangle covering the area of the text
- Open your Transparency menu (Window>Transparency)
- Select both the text and rectangle layers
- Click 'Make Mask' within the Transparency window.
- Select invert mask
Hope this helps!