Ubuntu Security Notice 841-1 - Arand Nash discovered that applications linked to GLib (e.g. Nautilus) did not correctly copy symlinks. If a user copied symlinks with GLib, the symlink target files would become world-writable, allowing local attackers to gain access to potentially sensitive information.
b17c57b39322b0668a28dff188e0f833a265e02c9fd772d12a1277c61008ab72