diff --git a/Library/Homebrew/dependency.rb b/Library/Homebrew/dependency.rb
index 44eaf57d0d..54d4f690eb 100644
--- a/Library/Homebrew/dependency.rb
+++ b/Library/Homebrew/dependency.rb
@@ -352,7 +352,13 @@ class UsesFromMacOSDependency < Dependency
         MacOSVersion.from_symbol(Homebrew::SimulateSystem.current_os)
       end
 
-      since_os = MacOSVersion.from_symbol(since_os_bounds)
+      since_os = begin
+        MacOSVersion.from_symbol(since_os_bounds)
+      rescue MacOSVersion::Error
+        # If we can't parse the bound, it means it's an unsupported macOS version
+        # so let's default to the oldest possible macOS version
+        Version::NULL
+      end
       return true if effective_os >= since_os
     end