Schroot before 1.6.13 had too permissive rules on chroot or session names, allowing a denial of service on the schroot service for all users that may start a schroot session.
{ "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro", "binaries": [ { "binary_name": "dchroot", "binary_version": "1.6.10-1ubuntu3+esm1" }, { "binary_name": "dchroot-dsa", "binary_version": "1.6.10-1ubuntu3+esm1" }, { "binary_name": "libsbuild-dev", "binary_version": "1.6.10-1ubuntu3+esm1" }, { "binary_name": "schroot", "binary_version": "1.6.10-1ubuntu3+esm1" }, { "binary_name": "schroot-common", "binary_version": "1.6.10-1ubuntu3+esm1" } ] }