diff --git a/src/Composer/Util/ProcessExecutor.php b/src/Composer/Util/ProcessExecutor.php
index b546b1529..6694a6e87 100644
--- a/src/Composer/Util/ProcessExecutor.php
+++ b/src/Composer/Util/ProcessExecutor.php
@@ -495,7 +495,9 @@ class ProcessExecutor
         }
 
         // New lines break cmd.exe command parsing
-        $argument = strtr($argument, "\n", ' ');
+        // and special chars like the fullwidth quote can be used to break out
+        // of parameter encoding via "Best Fit" encoding conversion
+        $argument = strtr($argument, ["\n" => ' ', '＂' => '"', '：' => ':', '／' => '/']);
 
         // In addition to whitespace, commas need quoting to preserve paths
         $quote = strpbrk($argument, " \t,") !== false;