diff --git a/src/Composer/Installer/BinaryInstaller.php b/src/Composer/Installer/BinaryInstaller.php
index 43254af61..91479bf58 100644
--- a/src/Composer/Installer/BinaryInstaller.php
+++ b/src/Composer/Installer/BinaryInstaller.php
@@ -359,6 +359,11 @@ namespace Composer;
 
 $globalsCode
 $streamProxyCode
+
+if (__FILE__ === realpath(\$_SERVER['SCRIPT_NAME'])) {
+    \$_SERVER['SCRIPT_NAME'] = realpath($binPathExported);
+}
+
 return include $binPathExported;
 
 PROXY;
diff --git a/tests/Composer/Test/Installer/BinaryInstallerTest.php b/tests/Composer/Test/Installer/BinaryInstallerTest.php
index 8b6d47243..0fe971793 100644
--- a/tests/Composer/Test/Installer/BinaryInstallerTest.php
+++ b/tests/Composer/Test/Installer/BinaryInstallerTest.php
@@ -110,6 +110,18 @@ EOL
 <?php declare(strict_types=1);
 
 echo 'success '.$_SERVER['argv'][1];
+EOL
+            ],
+            'php file which validates $_SERVER["SCRIPT_NAME"]' => [<<<'EOL'
+<?php
+if (__FILE__ === realpath($_SERVER['SCRIPT_NAME'])) {
+    echo 'success '.$_SERVER['argv'][1];
+} else {
+    fwrite(STDERR, "Test failure: __FILE__ does not match \$_SERVER['SCRIPT_NAME']\n");
+    fwrite(STDERR, "\t__FILE__:\t" . __FILE__ . "\n");
+    fwrite(STDERR, "\t\$_SERVER['SCRIPT_NAME']:\t" . $_SERVER['SCRIPT_NAME'] . "\n");
+    exit(1);
+}
 EOL
             ],
         ];