Gentoo Was Compromised On GitHub
In Summary : Unknown individuals were able to gain access to the Gentoo repositories on GitHub, including the modification of said reposit...
https://updatesinfosec.blogspot.com/2018/06/gentoo-was-compromised-on-github.html

Unknown individuals were able to gain access to the Gentoo repositories on GitHub, including the modification of said repositories.
While we don't normally cover all these individual security incidents, a Gentoo representative has asked we relay it here. Their public announcement warns, "All Gentoo code hosted on github should for the moment be considered compromised."
But for those relying upon the Gentoo.org infrastructure or Gentoo outside of GitHub, there is no known compromise, including the master Gentoo ebuild repository.
Their notice can be read on Gentoo.org. Gentoo is working with GitHub to properly address the situation.[...]
kindly refer the following link as follow up :
https://www.phoronix.com/scan.php?page=news_item&px=Gentoo-GitHub-Compromised