A flaw in libxml2 allows remote XML entity inclusion with default parser flags (i.e., when the caller did not request entity substitution, DTD validation, external DTD subset loading, or default DTD attributes). Depending on the context, this may expose a higher-risk attack surface in libxml2 not usually reachable with default parser flags, and expose content from local files, HTTP, or FTP servers (which might be otherwise unreachable).
https://www.tenable.com/blog/critical-vulnerability-fixes-available-for-juniper-devices
https://www.debian.org/security/2017/dsa-3952
https://source.android.com/security/bulletin/2017-06-01
https://security.gentoo.org/glsa/201711-01
https://git.gnome.org/browse/libxml2/commit/?id=90ccb58242866b0ba3edbef8fe44214a101c2b3e
https://bugzilla.redhat.com/show_bug.cgi?id=1462203