diff --git a/courses/admin.py b/courses/admin.py
index 3036c358..ea522116 100644
--- a/courses/admin.py
+++ b/courses/admin.py
@@ -19,6 +19,7 @@
     UserTaskAnswerFile,
     UserTaskAnswerOption,
 )
+from .models.content import looks_like_image_file
 
 # Admin-only captions for sections in app index
 CourseModule._meta.verbose_name = "Модуль"
@@ -148,6 +149,25 @@ class Meta:
         model = CourseTask
         fields = "__all__"
 
+    def clean(self):
+        cleaned_data = super().clean()
+        image_upload = cleaned_data.get("image_upload")
+        attachment_upload = cleaned_data.get("attachment_upload")
+        if image_upload and not looks_like_image_file(
+            mime_type=getattr(image_upload, "content_type", ""),
+            extension=getattr(image_upload, "name", "").rsplit(".", 1)[-1],
+        ):
+            self.add_error(
+                "image_upload",
+                "В поле изображения можно загрузить только файл изображения.",
+            )
+
+        # Preserve the fact that a file was provided so model validation
+        # doesn't add a second "required image" error for the same field.
+        self.instance._has_pending_image_upload = bool(image_upload)
+        self.instance._has_pending_attachment_upload = bool(attachment_upload)
+        return cleaned_data
+
 
 class CourseModuleAdminForm(forms.ModelForm):
     avatar_upload = forms.FileField(
diff --git a/courses/models/content.py b/courses/models/content.py
index ddbc37a6..8baec9db 100644
--- a/courses/models/content.py
+++ b/courses/models/content.py
@@ -16,6 +16,25 @@
 )
 from .course import Course
 
+ALLOWED_IMAGE_EXTENSIONS = {
+    "bmp",
+    "gif",
+    "jpg",
+    "jpeg",
+    "png",
+    "svg",
+    "webp",
+}
+
+
+def looks_like_image_file(*, mime_type: str | None = None, extension: str | None = None) -> bool:
+    normalized_mime_type = (mime_type or "").strip().lower()
+    if normalized_mime_type.startswith("image/"):
+        return True
+
+    normalized_extension = (extension or "").strip().lower().lstrip(".")
+    return normalized_extension in ALLOWED_IMAGE_EXTENSIONS
+
 
 class CourseModule(models.Model):
     course = models.ForeignKey(
@@ -273,11 +292,36 @@ def __str__(self):
     def _require_non_blank(value: str | None) -> bool:
         return bool(value and value.strip())
 
+    def _has_image_source(self) -> bool:
+        return self.image_file_id is not None or getattr(
+            self,
+            "_has_pending_image_upload",
+            False,
+        )
+
+    def _has_attachment_source(self) -> bool:
+        return self.attachment_file_id is not None or getattr(
+            self,
+            "_has_pending_attachment_upload",
+            False,
+        )
+
+    def _has_valid_image_file(self) -> bool:
+        if self.image_file_id is None:
+            return False
+        return looks_like_image_file(
+            mime_type=self.image_file.mime_type,
+            extension=self.image_file.extension,
+        )
+
     def clean(self):
         super().clean()
 
         errors = {}
 
+        if self.image_file_id is not None and not self._has_valid_image_file():
+            errors["image_file"] = "В поле изображения можно выбрать только файл изображения."
+
         if self.task_kind == CourseTaskKind.INFORMATIONAL:
             if self.informational_type == CourseTaskInformationalType.VIDEO_TEXT:
                 if not self._require_non_blank(self.body_text):
@@ -292,7 +336,7 @@ def clean(self):
                     errors["body_text"] = (
                         "Поле обязательно для типа 'Текст и изображение'."
                     )
-                if self.image_file_id is None:
+                if not self._has_image_source():
                     errors["image_file"] = (
                         "Поле обязательно для типа 'Текст и изображение'."
                     )
@@ -303,7 +347,7 @@ def clean(self):
                     errors["body_text"] = (
                         "Поле обязательно для типа вопроса 'Изображение и текст'."
                     )
-                if self.image_file_id is None:
+                if not self._has_image_source():
                     errors["image_file"] = (
                         "Поле обязательно для типа вопроса 'Изображение и текст'."
                     )
@@ -311,7 +355,7 @@ def clean(self):
                 if not self._require_non_blank(self.video_url):
                     errors["video_url"] = "Поле обязательно для типа вопроса 'Видео'."
             elif self.question_type == CourseTaskQuestionType.IMAGE:
-                if self.image_file_id is None:
+                if not self._has_image_source():
                     errors["image_file"] = (
                         "Поле обязательно для типа вопроса 'Изображение'."
                     )
@@ -320,7 +364,7 @@ def clean(self):
                     errors["body_text"] = (
                         "Поле обязательно для типа вопроса 'Текст с файлом'."
                     )
-                if self.attachment_file_id is None:
+                if not self._has_attachment_source():
                     errors["attachment_file"] = (
                         "Поле обязательно для типа вопроса 'Текст с файлом'."
                     )
diff --git a/courses/serializers.py b/courses/serializers.py
index 709df8fe..a1afb77e 100644
--- a/courses/serializers.py
+++ b/courses/serializers.py
@@ -27,6 +27,7 @@ class CourseAnalyticsStubSerializer(serializers.Serializer):
 
 class CourseCardSerializer(serializers.Serializer):
     id = serializers.IntegerField()
+    partner_program_id = serializers.IntegerField(allow_null=True)
     title = serializers.CharField()
     access_type = serializers.ChoiceField(choices=CourseAccessType.choices)
     status = serializers.ChoiceField(choices=CourseContentStatus.choices)
@@ -45,6 +46,7 @@ class CourseCardSerializer(serializers.Serializer):
 
 class CourseDetailSerializer(serializers.Serializer):
     id = serializers.IntegerField()
+    partner_program_id = serializers.IntegerField(allow_null=True)
     title = serializers.CharField()
     description = serializers.CharField(allow_blank=True)
     access_type = serializers.ChoiceField(choices=CourseAccessType.choices)
@@ -127,6 +129,7 @@ class CourseModuleStructureSerializer(serializers.Serializer):
 
 class CourseStructureSerializer(serializers.Serializer):
     course_id = serializers.IntegerField()
+    partner_program_id = serializers.IntegerField(allow_null=True)
     progress_status = serializers.ChoiceField(choices=ProgressStatus.choices)
     percent = serializers.IntegerField(min_value=0, max_value=100)
     modules = CourseModuleStructureSerializer(many=True)
diff --git a/courses/views.py b/courses/views.py
index 28c50c43..26820140 100644
--- a/courses/views.py
+++ b/courses/views.py
@@ -82,6 +82,7 @@ def get(self, request):
             data.append(
                 {
                     "id": course.id,
+                    "partner_program_id": course.partner_program_id,
                     "title": course.title,
                     "access_type": course.access_type,
                     "status": course.status,
@@ -122,6 +123,7 @@ def get(self, request, pk: int):
         serializer = CourseDetailSerializer(
             data={
                 "id": course.id,
+                "partner_program_id": course.partner_program_id,
                 "title": course.title,
                 "description": course.description,
                 "access_type": course.access_type,
@@ -255,6 +257,7 @@ def get(self, request, pk: int):
         serializer = CourseStructureSerializer(
             data={
                 "course_id": course.id,
+                "partner_program_id": course.partner_program_id,
                 "progress_status": course_progress_payload["status"],
                 "percent": course_progress_payload["percent"],
                 "modules": modules_payload,