Total vulnerabilities in the database
In the Linux kernel 4.15.x through 4.19.x before 4.19.2, map_write() in kernel/user_namespace.c allows privilege escalation because it mishandles nested user namespaces with more than 5 UID or GID ranges. A user who has CAP_SYS_ADMIN in an affected user namespace can bypass access controls on resources outside the namespace, as demonstrated by reading /etc/shadow. This occurs because an ID transformation takes place properly for the namespaced-to-kernel direction but not for the kernel-to-namespaced direction.
| Software | From | Fixed in |
|---|---|---|
| linux / linux_kernel | 4.15 | 4.19.2 |
| canonical / ubuntu_linux | 16.04 | 16.04.x |
| canonical / ubuntu_linux | 18.04 | 18.04.x |
| canonical / ubuntu_linux | 18.10 | 18.10.x |