diff --git a/api/http/handler/customtemplates/customtemplate_create.go b/api/http/handler/customtemplates/customtemplate_create.go
index 60727396b..f79aac9e9 100644
--- a/api/http/handler/customtemplates/customtemplate_create.go
+++ b/api/http/handler/customtemplates/customtemplate_create.go
@@ -3,6 +3,7 @@ package customtemplates
 import (
 	"errors"
 	"net/http"
+	"regexp"
 	"strconv"
 
 	"github.com/asaskevich/govalidator"
@@ -129,9 +130,20 @@ func (payload *customTemplateFromFileContentPayload) Validate(r *http.Request) e
 	if payload.Type != portainer.KubernetesStack && payload.Type != portainer.DockerSwarmStack && payload.Type != portainer.DockerComposeStack {
 		return errors.New("Invalid custom template type")
 	}
+	if !isValidNote(payload.Note) {
+		return errors.New("Invalid note. <img> tag is not supported")
+	}
 	return nil
 }
 
+func isValidNote(note string) bool {
+	if govalidator.IsNull(note) {
+		return true
+	}
+	match, _ := regexp.MatchString("<img", note)
+	return !match
+}
+
 func (handler *Handler) createCustomTemplateFromFileContent(r *http.Request) (*portainer.CustomTemplate, error) {
 	var payload customTemplateFromFileContentPayload
 	err := request.DecodeAndValidateJSONPayload(r, &payload)
@@ -218,6 +230,9 @@ func (payload *customTemplateFromGitRepositoryPayload) Validate(r *http.Request)
 	if payload.Type != portainer.DockerSwarmStack && payload.Type != portainer.DockerComposeStack {
 		return errors.New("Invalid custom template type")
 	}
+	if !isValidNote(payload.Note) {
+		return errors.New("Invalid note. <img> tag is not supported")
+	}
 	return nil
 }
 
@@ -285,6 +300,9 @@ func (payload *customTemplateFromFileUploadPayload) Validate(r *http.Request) er
 	payload.Logo = logo
 
 	note, _ := request.RetrieveMultiPartFormValue(r, "Note", true)
+	if !isValidNote(note) {
+		return errors.New("Invalid note. <img> tag is not supported")
+	}
 	payload.Note = note
 
 	typeNumeral, _ := request.RetrieveNumericMultiPartFormValue(r, "Type", true)
diff --git a/api/http/handler/customtemplates/customtemplate_update.go b/api/http/handler/customtemplates/customtemplate_update.go
index dcbb1dd65..0deac2c17 100644
--- a/api/http/handler/customtemplates/customtemplate_update.go
+++ b/api/http/handler/customtemplates/customtemplate_update.go
@@ -51,6 +51,9 @@ func (payload *customTemplateUpdatePayload) Validate(r *http.Request) error {
 	if govalidator.IsNull(payload.Description) {
 		return errors.New("Invalid custom template description")
 	}
+	if !isValidNote(payload.Note) {
+		return errors.New("Invalid note. <img> tag is not supported")
+	}
 	return nil
 }
 
diff --git a/app/portainer/models/tag.js b/app/portainer/models/tag.js
index 38bea58fb..ee3660ca9 100644
--- a/app/portainer/models/tag.js
+++ b/app/portainer/models/tag.js
@@ -1,4 +1,6 @@
+import _ from 'lodash-es';
+
 export function TagViewModel(data) {
   this.Id = data.ID;
-  this.Name = data.Name;
+  this.Name = _.escape(data.Name);
 }
diff --git a/app/portainer/models/team.js b/app/portainer/models/team.js
index c8d583133..617b36ce9 100644
--- a/app/portainer/models/team.js
+++ b/app/portainer/models/team.js
@@ -1,5 +1,7 @@
+import _ from 'lodash-es';
+
 export function TeamViewModel(data) {
   this.Id = data.Id;
-  this.Name = data.Name;
+  this.Name = _.escape(data.Name);
   this.Checked = false;
 }
diff --git a/app/portainer/services/api/customTemplate.js b/app/portainer/services/api/customTemplate.js
index 12d7d4688..641f4bcd4 100644
--- a/app/portainer/services/api/customTemplate.js
+++ b/app/portainer/services/api/customTemplate.js
@@ -3,15 +3,21 @@ import angular from 'angular';
 angular.module('portainer.app').factory('CustomTemplateService', CustomTemplateServiceFactory);
 
 /* @ngInject */
-function CustomTemplateServiceFactory(CustomTemplates, FileUploadService) {
+function CustomTemplateServiceFactory($sanitize, CustomTemplates, FileUploadService) {
   var service = {};
 
   service.customTemplate = function customTemplate(id) {
     return CustomTemplates.get({ id }).$promise;
   };
 
-  service.customTemplates = function customTemplates(type) {
-    return CustomTemplates.query({ type }).$promise;
+  service.customTemplates = async function customTemplates(type) {
+    const templates = await CustomTemplates.query({ type }).$promise;
+    templates.forEach((template) => {
+      if (template.Note) {
+        template.Note = $('<p>').html($sanitize(template.Note)).find('img').remove().end().html();
+      }
+    });
+    return templates;
   };
 
   service.remove = function remove(id) {
diff --git a/app/portainer/services/notifications.js b/app/portainer/services/notifications.js
index db401e4bd..51f98ff5e 100644
--- a/app/portainer/services/notifications.js
+++ b/app/portainer/services/notifications.js
@@ -1,3 +1,4 @@
+import _ from 'lodash-es';
 import toastr from 'toastr';
 
 angular.module('portainer.app').factory('Notifications', [
@@ -7,11 +8,11 @@ angular.module('portainer.app').factory('Notifications', [
     var service = {};
 
     service.success = function (title, text) {
-      toastr.success($sanitize(text), $sanitize(title));
+      toastr.success($sanitize(_.escape(text)), $sanitize(title));
     };
 
     service.warning = function (title, text) {
-      toastr.warning($sanitize(text), $sanitize(title), { timeOut: 6000 });
+      toastr.warning($sanitize(_.escape(text)), $sanitize(title), { timeOut: 6000 });
     };
 
     service.error = function (title, e, fallbackText) {
@@ -44,7 +45,7 @@ angular.module('portainer.app').factory('Notifications', [
       console.error(e);
 
       if (msg !== 'Invalid JWT token') {
-        toastr.error($sanitize(msg), $sanitize(title), { timeOut: 6000 });
+        toastr.error($sanitize(_.escape(msg)), $sanitize(title), { timeOut: 6000 });
       }
     };