diff --git a/Gemfile b/Gemfile
index 0d8fbf6..dcdbbf9 100644
--- a/Gemfile
+++ b/Gemfile
@@ -47,7 +47,7 @@ gem "geocoder", "~> 1.8.6"
 gem 'jbuilder', '~> 2.15.1'
 
 # json 3 removed keywords still used by Rails 7.x and ExecJS 2.9.
-gem 'json', '< 3'
+gem 'json', '< 4'
 
 # Logging (email)
 gem "exception_notification", "~> 5.0"
diff --git a/Gemfile.lock b/Gemfile.lock
index f18f033..f252792 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -159,7 +159,7 @@ GEM
       rails-dom-testing (>= 1, < 3)
       railties (>= 4.2.0)
       thor (>= 0.14, < 2.0)
-    json (2.21.2)
+    json (3.1.0)
     leaflet-rails (1.9.5)
       actionpack (>= 4.2.0)
       railties (>= 4.2.0)
@@ -340,7 +340,7 @@ DEPENDENCIES
   image_processing (~> 2.2)
   jbuilder (~> 2.15.1)
   jquery-rails (~> 4.6.1)
-  json (< 3)
+  json (< 4)
   leaflet-rails (~> 1.9.3)
   mini_magick
   mysql2 (~> 0.5.7)