The blinking ISO means the camera has reached its Auto ISO limit and still thinks more exposure may be needed. In Aperture Priority, the camera first lowers shutter speed as light drops, then raises ISO when the shutter gets too slow. Once ISO hits its maximum, it flashes to warn you it can’t increase sensitivity any further.

This doesn’t always mean your photo will be “wrong” — it means the camera’s meter, based on the current metering mode, believes the scene is underexposed for its target brightness.

What you can do:

• use a wider aperture if available
• allow a slower shutter speed if subject movement and camera shake permit
• raise the Auto ISO maximum if image quality is acceptable
• check metering mode, since it affects what the camera thinks is correct exposure
• add light or use a faster lens if you often shoot in very low light

So the kit lens isn’t necessarily defective; you’re likely just reaching the normal low-light limits of your current settings.