GStreamer Editing Services (gst-editing-services, libges) before 1.28.8 does not apply any restriction on the GStreamer pipeline description (bin-description) embedded in effect assets inside a .xges or .xptv project file. When a project is loaded via the XML formatter (ges-base-xml-formatter.c) or the Pitivi formatter (ges-pitivi-formatter.c), the asset-id field of each effect element is passed without sanitisation to ges_effect_from_description() and ges_effect_asset_id_get_type_and_bindesc() in ges/ges-effect-asset.c (lines ~300-415 in the vulnerable version). Both functions call gst_parse_bin_from_description_full() / gst_parse_bin_from_description() directly on the untrusted string, allowing instantiation of any registered GStreamer element factory. Properties on those elements (e.g. filesrc::location, souphttpsrc::location, filesink::location) can additionally be set by the project's children-properties XML attribute, which is applied verbatim via _set_child_property() (ges-base-xml-formatter.c ~line 550-571) through g_object_set_property() without any property denylist. The attack surface is greatly widened by the gesdemux GStreamer plugin (plugins/ges/gesplugin.c:42), registered at GST_RANK_PRIMARY. Advisory GStreamer-SA-2026-0090 (2026-10-08). Fix: gst-editing-services 1.28.8, MR !12647. Reporter: Sebastian Dröge (Centricular).