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EXPOSE instruction should not define an IP address or host-port mapping.
PropertyValue
SeverityWarning
CategoryCorrectness
DefaultEnabled

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Description

The EXPOSE instruction in a Dockerfile is used to indicate which ports the container listens on at runtime. It should not include an IP address or host-port mapping. Including an IP address or host-port mapping in the EXPOSE instruction does not actually publish the port and can be misleading. Use docker run -p or docker compose port mappings to bind host ports at runtime.

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Examples

Bad: 
FROM alpine
EXPOSE 127.0.0.1:80:80
Good: 
FROM alpine
EXPOSE 80
Bad: 
FROM alpine
EXPOSE 80:80
Good: 
FROM alpine
EXPOSE 80

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Reference