I believe it's public on their GitHub since 5 Aug 2018. https://github.com/gliderlabs/docker-alpine/issues/430
> 2019-03-01 - It was discovered that this issue was also reported and made public in their Github prior to our report, but was not flagged as a security issue and thus remained unresolved until it was rediscovered and reported by Cisco.
https://talosintelligence.com/vulnerability_reports/TALOS-20...