diff --git a/src/Composer/Util/Loop.php b/src/Composer/Util/Loop.php
index bed9151a9..3f85434de 100644
--- a/src/Composer/Util/Loop.php
+++ b/src/Composer/Util/Loop.php
@@ -25,8 +25,10 @@ class Loop
     private $httpDownloader;
     /** @var ProcessExecutor|null */
     private $processExecutor;
-    /** @var Promise[]|null */
-    private $currentPromises;
+    /** @var Promise[][] */
+    private $currentPromises = array();
+    /** @var int */
+    private $waitIndex = 0;
 
     public function __construct(HttpDownloader $httpDownloader, ProcessExecutor $processExecutor = null)
     {
@@ -67,7 +69,10 @@ class Loop
             }
         );
 
-        $this->currentPromises = $promises;
+        // keep track of every group of promises that is waited on, so abortJobs can
+        // cancel them all, even if wait() was called within a wait()
+        $waitIndex = $this->waitIndex++;
+        $this->currentPromises[$waitIndex] = $promises;
 
         if ($progress) {
             $totalJobs = 0;
@@ -101,7 +106,7 @@ class Loop
             usleep(5000);
         }
 
-        $this->currentPromises = null;
+        unset($this->currentPromises[$waitIndex]);
         if ($uncaught) {
             throw $uncaught;
         }
@@ -109,8 +114,8 @@ class Loop
 
     public function abortJobs()
     {
-        if ($this->currentPromises) {
-            foreach ($this->currentPromises as $promise) {
+        foreach ($this->currentPromises as $promiseGroup) {
+            foreach ($promiseGroup as $promise) {
                 $promise->cancel();
             }
         }