A Privilege Context Switching issue was discovered in join.c in Firejail 0.9.68. By crafting a bogus Firejail container that is accepted by the Firejail setuid-root program as a join target, a local attacker can enter an environment in which the Linux user namespace is still the initial user namespace, the NO_NEW_PRIVS prctl is not activated, and the entered mount namespace is under the attackers control. In this way, the filesystem layout can be adjusted to gain root privileges through execution of available setuid-root binaries such as su or sudo.
The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Firejail | Firejail_project | 0.9.68 (including) | 0.9.68 (including) |
| Firejail | Ubuntu | bionic | * |
| Firejail | Ubuntu | impish | * |
| Firejail | Ubuntu | kinetic | * |
| Firejail | Ubuntu | lunar | * |
| Firejail | Ubuntu | mantic | * |