SECURITY: Prevent ReDoS in user agent parsing (discourse#20002)

Co-authored-by: Penar Musaraj <[email protected]>
RickyC0626-forks · Jan 25, 2023 · 6d92c3c · 6d92c3c
1 parent b32db6f
commit 6d92c3c
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/lib/mobile_detection.rb b/lib/mobile_detection.rb
@@ -36,7 +36,9 @@ def self.ios_device?(user_agent)
     Firefox\/1[0-9][0-9]
   }x
 
+  USER_AGENT_MAX_LENGTH = 400
+
   def self.modern_mobile_device?(user_agent)
-    user_agent.match?(MODERN_MOBILE_REGEX)
+    user_agent[0...USER_AGENT_MAX_LENGTH].match?(MODERN_MOBILE_REGEX)
   end
 end