rbash in Bash before 4.4-beta2 did not prevent the shell user from modifying BASH_CMDS, thus allowing the user to execute any command with the permissions of the shell.
{ "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro", "ubuntu_priority": "low", "binaries": [ { "binary_name": "bash", "binary_version": "4.3-7ubuntu1.8+esm1" }, { "binary_name": "bash-builtins", "binary_version": "4.3-7ubuntu1.8+esm1" }, { "binary_name": "bash-dbgsym", "binary_version": "4.3-7ubuntu1.8+esm1" }, { "binary_name": "bash-doc", "binary_version": "4.3-7ubuntu1.8+esm1" }, { "binary_name": "bash-static", "binary_version": "4.3-7ubuntu1.8+esm1" }, { "binary_name": "bash-static-dbgsym", "binary_version": "4.3-7ubuntu1.8+esm1" } ] }
{ "availability": "No subscription required", "ubuntu_priority": "low", "binaries": [ { "binary_name": "bash", "binary_version": "4.3-14ubuntu1.4" }, { "binary_name": "bash-builtins", "binary_version": "4.3-14ubuntu1.4" }, { "binary_name": "bash-dbgsym", "binary_version": "4.3-14ubuntu1.4" }, { "binary_name": "bash-doc", "binary_version": "4.3-14ubuntu1.4" }, { "binary_name": "bash-static", "binary_version": "4.3-14ubuntu1.4" }, { "binary_name": "bash-static-dbgsym", "binary_version": "4.3-14ubuntu1.4" } ] }
{ "availability": "No subscription required", "ubuntu_priority": "low", "binaries": [ { "binary_name": "bash", "binary_version": "4.4.18-2ubuntu1" }, { "binary_name": "bash-builtins", "binary_version": "4.4.18-2ubuntu1" }, { "binary_name": "bash-builtins-dbgsym", "binary_version": "4.4.18-2ubuntu1" }, { "binary_name": "bash-dbgsym", "binary_version": "4.4.18-2ubuntu1" }, { "binary_name": "bash-doc", "binary_version": "4.4.18-2ubuntu1" }, { "binary_name": "bash-static", "binary_version": "4.4.18-2ubuntu1" }, { "binary_name": "bash-static-dbgsym", "binary_version": "4.4.18-2ubuntu1" } ] }