diff --git a/src/Composer/Package/Loader/ValidatingArrayLoader.php b/src/Composer/Package/Loader/ValidatingArrayLoader.php
index b5a11fc63..25d1109a4 100644
--- a/src/Composer/Package/Loader/ValidatingArrayLoader.php
+++ b/src/Composer/Package/Loader/ValidatingArrayLoader.php
@@ -76,7 +76,7 @@ class ValidatingArrayLoader implements LoaderInterface
         $this->validateString('time');
         if (!empty($this->config['time'])) {
             try {
-                $date = new \DateTime($this->config['time']);
+                $date = new \DateTime($this->config['time'], new \DateTimeZone('UTC'));
             } catch (\Exception $e) {
                 $this->errors[] = 'time : invalid value ('.$this->config['time'].'): '.$e->getMessage();
                 unset($this->config['time']);
diff --git a/src/Composer/Package/Locker.php b/src/Composer/Package/Locker.php
index 9ff8dc049..a474f654e 100644
--- a/src/Composer/Package/Locker.php
+++ b/src/Composer/Package/Locker.php
@@ -292,7 +292,8 @@ class Locker
                     $sourceRef = $package->getSourceReference() ?: $package->getDistReference();
                     $process = new ProcessExecutor();
                     if (0 === $process->execute('git log -n1 --pretty=%ct '.escapeshellarg($sourceRef), $output, $path)) {
-                        $spec['time'] = trim($output);
+                        $datetime = new \DateTime('@'.$output, new \DateTimeZone('UTC'));
+                        $spec['time'] = $datetime->format('Y-m-d H:i:s');
                     }
                 }
             }
diff --git a/src/Composer/Repository/Vcs/GitDriver.php b/src/Composer/Repository/Vcs/GitDriver.php
index 8c0290555..b5abbd9c4 100644
--- a/src/Composer/Repository/Vcs/GitDriver.php
+++ b/src/Composer/Repository/Vcs/GitDriver.php
@@ -140,7 +140,7 @@ class GitDriver extends VcsDriver
 
             if (!isset($composer['time'])) {
                 $this->process->execute(sprintf('git log -1 --format=%%at %s', escapeshellarg($identifier)), $output, $this->repoDir);
-                $date = new \DateTime('@'.trim($output));
+                $date = new \DateTime('@'.trim($output), new \DateTimeZone('UTC'));
                 $composer['time'] = $date->format('Y-m-d H:i:s');
             }
             $this->infoCache[$identifier] = $composer;
diff --git a/src/Composer/Repository/Vcs/HgDriver.php b/src/Composer/Repository/Vcs/HgDriver.php
index 69cef405f..4c09eca35 100755
--- a/src/Composer/Repository/Vcs/HgDriver.php
+++ b/src/Composer/Repository/Vcs/HgDriver.php
@@ -127,7 +127,7 @@ class HgDriver extends VcsDriver
 
             if (!isset($composer['time'])) {
                 $this->process->execute(sprintf('hg log --template "{date|rfc822date}" -r %s', escapeshellarg($identifier)), $output, $this->repoDir);
-                $date = new \DateTime(trim($output));
+                $date = new \DateTime(trim($output), new \DateTimeZone('UTC'));
                 $composer['time'] = $date->format('Y-m-d H:i:s');
             }
             $this->infoCache[$identifier] = $composer;
diff --git a/src/Composer/Repository/Vcs/SvnDriver.php b/src/Composer/Repository/Vcs/SvnDriver.php
index 7477d6fdf..a3b2b37e2 100755
--- a/src/Composer/Repository/Vcs/SvnDriver.php
+++ b/src/Composer/Repository/Vcs/SvnDriver.php
@@ -138,7 +138,7 @@ class SvnDriver extends VcsDriver
                 $output = $this->execute('svn info', $this->baseUrl . $path . $rev);
                 foreach ($this->process->splitLines($output) as $line) {
                     if ($line && preg_match('{^Last Changed Date: ([^(]+)}', $line, $match)) {
-                        $date = new \DateTime($match[1]);
+                        $date = new \DateTime($match[1], new \DateTimeZone('UTC'));
                         $composer['time'] = $date->format('Y-m-d H:i:s');
                         break;
                     }