diff --git a/CHANGES.md b/CHANGES.md
index 2b75de8ad..fff4250c8 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -17,6 +17,7 @@
 - Fix change opacity in colorpicker cause bugged color [Taiga #4154](https://tree.taiga.io/project/penpot/issue/4154)
 - Fix gradient colors don't arrive in recent colors palette (https://tree.taiga.io/project/penpot/issue/4155)
 - Fix selected colors allow gradients in shadows [Taiga #4156](https://tree.taiga.io/project/penpot/issue/4156)
+- Fix import files with unexpected format or invalid content [Taiga #4136](https://tree.taiga.io/project/penpot/issue/4136)
 
 ## 1.15.3-beta
 
diff --git a/frontend/src/app/main/ui/dashboard/import.cljs b/frontend/src/app/main/ui/dashboard/import.cljs
index 565dda8fb..bde0f44f3 100644
--- a/frontend/src/app/main/ui/dashboard/import.cljs
+++ b/frontend/src/app/main/ui/dashboard/import.cljs
@@ -304,7 +304,8 @@
         success-files (->> @state :files (filter #(and (= (:status %) :import-finish) (empty? (:errors %)))) count)
         pending-analysis? (> (->> @state :files (filter #(= (:status %) :analyzing)) count) 0)
         pending-import? (> (->> @state :files (filter #(= (:status %) :importing)) count) 0)
-        files (->> (:files @state) (filterv (comp not :deleted?)))]
+        files (->> (:files @state) (filterv (comp not :deleted?)))
+        valid-files? (> (->> files (filterv (fn [x] (not= (:status x) :analyze-error))) count) 0)]
 
     (mf/use-effect
      (fn []
@@ -359,7 +360,7 @@
            {:class "primary"
             :type "button"
             :value (tr "labels.continue")
-            :disabled pending-analysis?
+            :disabled (or pending-analysis? (not valid-files?))
             :on-click handle-continue}])
 
         (when (= :importing (:status @state))
@@ -367,5 +368,5 @@
            {:class "primary"
             :type "button"
             :value (tr "labels.accept")
-            :disabled pending-import?
+            :disabled (or pending-import? (not valid-files?))
             :on-click handle-accept}])]]]]))
diff --git a/frontend/src/app/worker/import.cljs b/frontend/src/app/worker/import.cljs
index aff53ab5b..a1538e4b4 100644
--- a/frontend/src/app/worker/import.cljs
+++ b/frontend/src/app/worker/import.cljs
@@ -19,6 +19,7 @@
    [app.common.uuid :as uuid]
    [app.main.repo :as rp]
    [app.util.http :as http]
+   [app.util.i18n :as i18n :refer [tr]]
    [app.util.import.parser :as cip]
    [app.util.json :as json]
    [app.util.webapi :as wapi]
@@ -526,7 +527,8 @@
         sg (areduce u8 i ret "" (str ret (if (zero? i) "" " ") (.toString (aget u8 i) 8)))]
     (case sg
       "120 113 3 4" "application/zip"
-      "application/octet-stream")))
+      "1 13 32 206" "application/octet-stream"
+      "other")))
 
 (defmethod impl/handler :analyze-import
   [{:keys [files]}]
@@ -560,8 +562,15 @@
                                            :file-id file-id
                                            :files {file-id {:name (:name file)}}
                                            :status :ready}
-                                    :type "application/octet-stream"})))))
-                 (rx/catch #(rx/of {:uri (:uri file) :error (.-message %)}))))))))
+                                    :type "application/octet-stream"}))))
+                  (->> st
+                       (rx/filter (fn [data] (= "other" (:type data))))
+                       (rx/map (fn [_]
+                                 {:uri (:uri file)
+                                  :error (tr "dashboard.import.analyze-error")}))))
+                 (rx/catch (fn [data]
+                             (let [error (or (.-message data) (tr "dashboard.import.analyze-error"))]
+                               (rx/of {:uri (:uri file) :error error}))))))))))
 
 (defmethod impl/handler :import-files
   [{:keys [project-id files]}]