daemon/Greeter.cpp in sddm before 0.13.0 does not properly disable the KDE crash handler, which allows local users to gain privileges by crashing a greeter when using certain themes, as demonstrated by the plasma-workspace breeze theme.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Fedora | Fedoraproject | 22 (including) | 22 (including) |
| Sddm | Ubuntu | artful | * |
| Sddm | Ubuntu | upstream | * |
| Sddm | Ubuntu | vivid | * |
| Sddm | Ubuntu | wily | * |
| Sddm | Ubuntu | yakkety | * |
| Sddm | Ubuntu | zesty | * |