The XListFonts function in X.org libX11 before 1.6.4 might allow remote X servers to gain privileges via vectors involving length fields, which trigger out-of-bounds write operations.
| Software | From | Fixed in |
|---|---|---|
| fedoraproject / fedora | 25 | 25.x |
| x.org / libx11 | - | 1.6.3.x |