Docker Hub password authentication randomly fails requiring tokens

Docker Hub randomly stops accepting passwords for private repository authentication, causing Snyk scans to fail with 'authentication credentials not recognized' errors. This happens without warning and affects CI/CD pipelines.

Generate an access token from Docker Hub Account Settings > Security section. Use the token instead of password in CI/CD by setting DOCKER_USERNAME and DOCKER_TOKEN environment variables. Test with `docker login` before configuring Snyk.