diff --git a/appengine/flexible/ruby31-and-earlier/static_files/sinatra/Gemfile.lock b/appengine/flexible/ruby31-and-earlier/static_files/sinatra/Gemfile.lock
index c36ac57ec..f4ae5a8e0 100644
--- a/appengine/flexible/ruby31-and-earlier/static_files/sinatra/Gemfile.lock
+++ b/appengine/flexible/ruby31-and-earlier/static_files/sinatra/Gemfile.lock
@@ -3,6 +3,7 @@ GEM
   specs:
     addressable (2.5.2)
       public_suffix (>= 2.0.2, < 4.0)
+    base64 (0.3.0)
     capybara (3.4.2)
       addressable
       mini_mime (>= 0.1.3)
@@ -20,9 +21,11 @@ GEM
       concurrent-ruby (~> 1.1)
       webrick (~> 1.7)
       websocket-driver (>= 0.6, < 0.8)
+    logger (1.7.0)
     mini_mime (1.0.0)
     mini_portile2 (2.8.6)
-    mustermann (1.0.2)
+    mustermann (3.0.4)
+      ruby2_keywords (~> 0.0.1)
     nio4r (2.7.0)
     nokogiri (1.16.5)
       mini_portile2 (~> 2.8.2)
@@ -31,11 +34,16 @@ GEM
     puma (5.6.8)
       nio4r (~> 2.0)
     racc (1.7.3)
-    rack (2.2.8.1)
-    rack-protection (2.0.3)
-      rack
-    rack-test (1.1.0)
-      rack (>= 1.0, < 3)
+    rack (3.2.3)
+    rack-protection (4.2.0)
+      base64 (>= 0.1.0)
+      logger (>= 1.6.0)
+      rack (>= 3.0.0, < 4)
+    rack-session (2.1.1)
+      base64 (>= 0.1.0)
+      rack (>= 3.0.0)
+    rack-test (2.2.0)
+      rack (>= 1.3)
     rspec (3.7.0)
       rspec-core (~> 3.7.0)
       rspec-expectations (~> 3.7.0)
@@ -51,16 +59,19 @@ GEM
     rspec-support (3.7.1)
     rspec_junit_formatter (0.6.0)
       rspec-core (>= 2, < 4, != 2.12.0)
-    sinatra (2.0.3)
-      mustermann (~> 1.0)
-      rack (~> 2.0)
-      rack-protection (= 2.0.3)
+    ruby2_keywords (0.0.5)
+    sinatra (4.2.0)
+      logger (>= 1.6.0)
+      mustermann (~> 3.0)
+      rack (>= 3.0.0, < 4)
+      rack-protection (= 4.2.0)
+      rack-session (>= 2.0.0, < 3)
       tilt (~> 2.0)
     slim (3.0.9)
       temple (>= 0.7.6, < 0.9)
       tilt (>= 1.3.3, < 2.1)
     temple (0.8.0)
-    tilt (2.0.8)
+    tilt (2.0.11)
     webrick (1.8.2)
     websocket-driver (0.7.6)
       websocket-extensions (>= 0.1.0)