Insufficient sanitization of environment variables passed to rsync can bypass the restrictions imposed by rssh, a restricted shell that should restrict users to perform only rsync operations, resulting in the execution of arbitrary shell commands.Referenceshttps://www.debian.org/security/2019/dsa-4382https://lists.debian.org/debian-lts-announce/2019/02/msg00007.htmlhttp://www.securityfocus.com/bid/106839https://tracker.debian.org/news/1026713/accepted-rssh-234-5deb9u2-source-amd64-into-stable-embargoed-stable/https://usn.ubuntu.com/3946-1/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HO3MDU3AH5SLYBKHH5PJ6PHC63ASIF42/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/T42YYNWJZG422GATWAHAEK4A24OKY557/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KR2OHTHMJVV4DO3HDRFQQZ5JENHDJQEN/https://security.gentoo.org/glsa/202007-29http://seclists.org/fulldisclosure/2021/May/78
