diff --git a/src/Composer/Repository/Vcs/GitBitbucketDriver.php b/src/Composer/Repository/Vcs/GitBitbucketDriver.php
index c3b8dd8c4..ff9aecafc 100644
--- a/src/Composer/Repository/Vcs/GitBitbucketDriver.php
+++ b/src/Composer/Repository/Vcs/GitBitbucketDriver.php
@@ -153,6 +153,9 @@ class GitBitbucketDriver extends VcsDriver
 
             if ($composer !== null) {
                 // specials for bitbucket
+                if (isset($composer['support']) && !is_array($composer['support'])) {
+                    $composer['support'] = [];
+                }
                 if (!isset($composer['support']['source'])) {
                     $label = array_search(
                         $identifier,
diff --git a/src/Composer/Repository/Vcs/GitHubDriver.php b/src/Composer/Repository/Vcs/GitHubDriver.php
index 98dbf989a..122b03fa7 100644
--- a/src/Composer/Repository/Vcs/GitHubDriver.php
+++ b/src/Composer/Repository/Vcs/GitHubDriver.php
@@ -174,6 +174,9 @@ class GitHubDriver extends VcsDriver
 
             if ($composer !== null) {
                 // specials for github
+                if (isset($composer['support']) && !is_array($composer['support'])) {
+                    $composer['support'] = [];
+                }
                 if (!isset($composer['support']['source'])) {
                     $label = array_search($identifier, $this->getTags()) ?: array_search($identifier, $this->getBranches()) ?: $identifier;
                     $composer['support']['source'] = sprintf('https://%s/%s/%s/tree/%s', $this->originUrl, $this->owner, $this->repository, $label);
diff --git a/src/Composer/Repository/Vcs/GitLabDriver.php b/src/Composer/Repository/Vcs/GitLabDriver.php
index 77b183e0b..1e13154c5 100644
--- a/src/Composer/Repository/Vcs/GitLabDriver.php
+++ b/src/Composer/Repository/Vcs/GitLabDriver.php
@@ -167,6 +167,9 @@ class GitLabDriver extends VcsDriver
 
             if (null !== $composer) {
                 // specials for gitlab (this data is only available if authentication is provided)
+                if (isset($composer['support']) && !is_array($composer['support'])) {
+                    $composer['support'] = [];
+                }
                 if (!isset($composer['support']['source']) && isset($this->project['web_url'])) {
                     $label = array_search($identifier, $this->getTags(), true) ?: array_search($identifier, $this->getBranches(), true) ?: $identifier;
                     $composer['support']['source'] = sprintf('%s/-/tree/%s', $this->project['web_url'], $label);
diff --git a/tests/Composer/Test/Repository/Vcs/GitBitbucketDriverTest.php b/tests/Composer/Test/Repository/Vcs/GitBitbucketDriverTest.php
index 3a35cd28e..5050b0fb4 100644
--- a/tests/Composer/Test/Repository/Vcs/GitBitbucketDriverTest.php
+++ b/tests/Composer/Test/Repository/Vcs/GitBitbucketDriverTest.php
@@ -14,6 +14,8 @@ namespace Composer\Test\Repository\Vcs;
 
 use Composer\Config;
 use Composer\Repository\Vcs\GitBitbucketDriver;
+use Composer\Repository\Vcs\GitHubDriver;
+use Composer\Test\Mock\HttpDownloaderMock;
 use Composer\Test\TestCase;
 use Composer\Util\Filesystem;
 use Composer\Util\ProcessExecutor;
@@ -28,7 +30,7 @@ class GitBitbucketDriverTest extends TestCase
     private $io;
     /** @var Config */
     private $config;
-    /** @var \Composer\Util\HttpDownloader&\PHPUnit\Framework\MockObject\MockObject */
+    /** @var HttpDownloaderMock */
     private $httpDownloader;
     /** @var string */
     private $home;
@@ -46,9 +48,7 @@ class GitBitbucketDriverTest extends TestCase
             ],
         ]);
 
-        $this->httpDownloader = $this->getMockBuilder('Composer\Util\HttpDownloader')
-            ->disableOriginalConstructor()
-            ->getMock();
+        $this->httpDownloader = $this->getHttpDownloaderMock($this->io, $this->config);;
     }
 
     protected function tearDown(): void
@@ -83,15 +83,9 @@ class GitBitbucketDriverTest extends TestCase
         self::expectException('RuntimeException');
         self::expectExceptionMessage('https://bitbucket.org/user/repo.git does not appear to be a git repository, use https://bitbucket.org/user/repo but remember that Bitbucket no longer supports the mercurial repositories. https://bitbucket.org/blog/sunsetting-mercurial-support-in-bitbucket');
 
-        $this->httpDownloader->expects($this->once())
-            ->method('get')
-            ->with(
-                $url = 'https://api.bitbucket.org/2.0/repositories/user/repo?fields=-project%2C-owner',
-                []
-            )
-            ->willReturn(
-                new Response(['url' => $url], 200, [], '{"scm":"hg","website":"","has_wiki":false,"name":"repo","links":{"branches":{"href":"https:\/\/api.bitbucket.org\/2.0\/repositories\/user\/repo\/refs\/branches"},"tags":{"href":"https:\/\/api.bitbucket.org\/2.0\/repositories\/user\/repo\/refs\/tags"},"clone":[{"href":"https:\/\/user@bitbucket.org\/user\/repo","name":"https"},{"href":"ssh:\/\/hg@bitbucket.org\/user\/repo","name":"ssh"}],"html":{"href":"https:\/\/bitbucket.org\/user\/repo"}},"language":"php","created_on":"2015-02-18T16:22:24.688+00:00","updated_on":"2016-05-17T13:20:21.993+00:00","is_private":true,"has_issues":false}')
-            );
+        $this->httpDownloader->expects([
+            ['url' => 'https://api.bitbucket.org/2.0/repositories/user/repo?fields=-project%2C-owner', 'body' => '{"scm":"hg","website":"","has_wiki":false,"name":"repo","links":{"branches":{"href":"https:\/\/api.bitbucket.org\/2.0\/repositories\/user\/repo\/refs\/branches"},"tags":{"href":"https:\/\/api.bitbucket.org\/2.0\/repositories\/user\/repo\/refs\/tags"},"clone":[{"href":"https:\/\/user@bitbucket.org\/user\/repo","name":"https"},{"href":"ssh:\/\/hg@bitbucket.org\/user\/repo","name":"ssh"}],"html":{"href":"https:\/\/bitbucket.org\/user\/repo"}},"language":"php","created_on":"2015-02-18T16:22:24.688+00:00","updated_on":"2016-05-17T13:20:21.993+00:00","is_private":true,"has_issues":false}']
+        ], true);
 
         $driver = $this->getDriver(['url' => 'https://bitbucket.org/user/repo.git']);
 
@@ -109,32 +103,13 @@ class GitBitbucketDriverTest extends TestCase
             'https://api.bitbucket.org/2.0/repositories/user/repo/src/main/composer.json',
             'https://api.bitbucket.org/2.0/repositories/user/repo/commit/main?fields=date',
         ];
-        $this->httpDownloader->expects($this->any())
-            ->method('get')
-            ->withConsecutive(
-                [
-                    $urls[0], [],
-                ],
-                [
-                    $urls[1], [],
-                ],
-                [
-                    $urls[2], [],
-                ],
-                [
-                    $urls[3], [],
-                ],
-                [
-                    $urls[4], [],
-                ]
-            )
-            ->willReturnOnConsecutiveCalls(
-                new Response(['url' => $urls[0]], 200, [], '{"mainbranch": {"name": "main"}, "scm":"git","website":"","has_wiki":false,"name":"repo","links":{"branches":{"href":"https:\/\/api.bitbucket.org\/2.0\/repositories\/user\/repo\/refs\/branches"},"tags":{"href":"https:\/\/api.bitbucket.org\/2.0\/repositories\/user\/repo\/refs\/tags"},"clone":[{"href":"https:\/\/user@bitbucket.org\/user\/repo.git","name":"https"},{"href":"ssh:\/\/git@bitbucket.org\/user\/repo.git","name":"ssh"}],"html":{"href":"https:\/\/bitbucket.org\/user\/repo"}},"language":"php","created_on":"2015-02-18T16:22:24.688+00:00","updated_on":"2016-05-17T13:20:21.993+00:00","is_private":true,"has_issues":false}'),
-                new Response(['url' => $urls[1]], 200, [], '{"values":[{"name":"1.0.1","target":{"hash":"9b78a3932143497c519e49b8241083838c8ff8a1"}},{"name":"1.0.0","target":{"hash":"d3393d514318a9267d2f8ebbf463a9aaa389f8eb"}}]}'),
-                new Response(['url' => $urls[2]], 200, [], '{"values":[{"name":"main","target":{"hash":"937992d19d72b5116c3e8c4a04f960e5fa270b22"}}]}'),
-                new Response(['url' => $urls[3]], 200, [], '{"name": "user/repo","description": "test repo","license": "GPL","authors": [{"name": "Name","email": "local@domain.tld"}],"require": {"creator/package": "^1.0"},"require-dev": {"phpunit/phpunit": "~4.8"}}'),
-                new Response(['url' => $urls[4]], 200, [], '{"date": "2016-05-17T13:19:52+00:00"}')
-            );
+        $this->httpDownloader->expects([
+            ['url' => $urls[0], 'body' => '{"mainbranch": {"name": "main"}, "scm":"git","website":"","has_wiki":false,"name":"repo","links":{"branches":{"href":"https:\/\/api.bitbucket.org\/2.0\/repositories\/user\/repo\/refs\/branches"},"tags":{"href":"https:\/\/api.bitbucket.org\/2.0\/repositories\/user\/repo\/refs\/tags"},"clone":[{"href":"https:\/\/user@bitbucket.org\/user\/repo.git","name":"https"},{"href":"ssh:\/\/git@bitbucket.org\/user\/repo.git","name":"ssh"}],"html":{"href":"https:\/\/bitbucket.org\/user\/repo"}},"language":"php","created_on":"2015-02-18T16:22:24.688+00:00","updated_on":"2016-05-17T13:20:21.993+00:00","is_private":true,"has_issues":false}'],
+            ['url' => $urls[1], 'body' => '{"values":[{"name":"1.0.1","target":{"hash":"9b78a3932143497c519e49b8241083838c8ff8a1"}},{"name":"1.0.0","target":{"hash":"d3393d514318a9267d2f8ebbf463a9aaa389f8eb"}}]}'],
+            ['url' => $urls[2], 'body' => '{"values":[{"name":"main","target":{"hash":"937992d19d72b5116c3e8c4a04f960e5fa270b22"}}]}'],
+            ['url' => $urls[3], 'body' => '{"name": "user/repo","description": "test repo","license": "GPL","authors": [{"name": "Name","email": "local@domain.tld"}],"require": {"creator/package": "^1.0"},"require-dev": {"phpunit/phpunit": "~4.8"}}'],
+            ['url' => $urls[4], 'body' => '{"date": "2016-05-17T13:19:52+00:00"}'],
+        ], true);
 
         $this->assertEquals(
             'main',
@@ -218,6 +193,34 @@ class GitBitbucketDriverTest extends TestCase
         $driver->initialize();
     }
 
+    public function testInvalidSupportData(): void
+    {
+        $repoUrl = 'https://bitbucket.org/user/repo.git';
+
+        $driver = $this->getDriver(['url' => $repoUrl]);
+
+        $urls = [
+            'https://api.bitbucket.org/2.0/repositories/user/repo?fields=-project%2C-owner',
+            'https://api.bitbucket.org/2.0/repositories/user/repo/src/main/composer.json',
+            'https://api.bitbucket.org/2.0/repositories/user/repo/commit/main?fields=date',
+            'https://api.bitbucket.org/2.0/repositories/user/repo/refs/tags?pagelen=100&fields=values.name%2Cvalues.target.hash%2Cnext&sort=-target.date',
+            'https://api.bitbucket.org/2.0/repositories/user/repo/refs/branches?pagelen=100&fields=values.name%2Cvalues.target.hash%2Cvalues.heads%2Cnext&sort=-target.date',
+        ];
+        $this->httpDownloader->expects([
+            ['url' => $urls[0], 'body' => '{"mainbranch": {"name": "main"}, "scm":"git","website":"","has_wiki":false,"name":"repo","links":{"branches":{"href":"https:\/\/api.bitbucket.org\/2.0\/repositories\/user\/repo\/refs\/branches"},"tags":{"href":"https:\/\/api.bitbucket.org\/2.0\/repositories\/user\/repo\/refs\/tags"},"clone":[{"href":"https:\/\/user@bitbucket.org\/user\/repo.git","name":"https"},{"href":"ssh:\/\/git@bitbucket.org\/user\/repo.git","name":"ssh"}],"html":{"href":"https:\/\/bitbucket.org\/user\/repo"}},"language":"php","created_on":"2015-02-18T16:22:24.688+00:00","updated_on":"2016-05-17T13:20:21.993+00:00","is_private":true,"has_issues":false}'],
+            ['url' => $urls[1], 'body' => '{"support": "' . $repoUrl . '"}'],
+            ['url' => $urls[2], 'body' => '{"date": "2016-05-17T13:19:52+00:00"}'],
+            ['url' => $urls[3], 'body' => '{"values":[{"name":"1.0.1","target":{"hash":"9b78a3932143497c519e49b8241083838c8ff8a1"}},{"name":"1.0.0","target":{"hash":"d3393d514318a9267d2f8ebbf463a9aaa389f8eb"}}]}'],
+            ['url' => $urls[4], 'body' => '{"values":[{"name":"main","target":{"hash":"937992d19d72b5116c3e8c4a04f960e5fa270b22"}}]}'],
+        ], true);
+
+        $driver->getRootIdentifier();
+        $data = $driver->getComposerInformation('main');
+
+        $this->assertIsArray($data);
+        $this->assertSame('https://bitbucket.org/user/repo/src/937992d19d72b5116c3e8c4a04f960e5fa270b22/?at=main', $data['support']['source']);
+    }
+
     public function testSupports(): void
     {
         $this->assertTrue(
diff --git a/tests/Composer/Test/Repository/Vcs/GitHubDriverTest.php b/tests/Composer/Test/Repository/Vcs/GitHubDriverTest.php
index 68cf5e295..8431a1b49 100644
--- a/tests/Composer/Test/Repository/Vcs/GitHubDriverTest.php
+++ b/tests/Composer/Test/Repository/Vcs/GitHubDriverTest.php
@@ -199,6 +199,44 @@ class GitHubDriverTest extends TestCase
         $this->assertArrayNotHasKey('abandoned', $data);
     }
 
+    public function testInvalidSupportData(): void
+    {
+        $repoUrl = 'http://github.com/composer/packagist';
+        $repoApiUrl = 'https://api.github.com/repos/composer/packagist';
+        $identifier = 'feature/3.2-foo';
+        $sha = 'SOMESHA';
+
+        $io = $this->getMockBuilder('Composer\IO\IOInterface')->getMock();
+        $io->expects($this->any())
+            ->method('isInteractive')
+            ->will($this->returnValue(true));
+
+        $httpDownloader = $this->getHttpDownloaderMock($io, $this->config);
+        $httpDownloader->expects(
+            [
+                ['url' => $repoApiUrl, 'body' => '{"master_branch": "test_master", "owner": {"login": "composer"}, "name": "packagist"}'],
+                ['url' => 'https://api.github.com/repos/composer/packagist/contents/composer.json?ref=feature%2F3.2-foo', 'body' => '{"encoding":"base64","content":"'.base64_encode('{"support": "'.$repoUrl.'" }').'"}'],
+                ['url' => 'https://api.github.com/repos/composer/packagist/commits/feature%2F3.2-foo', 'body' => '{"commit": {"committer":{ "date": "2012-09-10"}}}'],
+                ['url' => 'https://api.github.com/repos/composer/packagist/contents/.github/FUNDING.yml', 'body' => '{"encoding": "base64", "content": "'.base64_encode("custom: https://example.com").'"}'],
+            ],
+            true
+        );
+
+        $repoConfig = [
+            'url' => $repoUrl,
+        ];
+
+        $gitHubDriver = new GitHubDriver($repoConfig, $io, $this->config, $httpDownloader, $this->getProcessExecutorMock());
+        $gitHubDriver->initialize();
+        $this->setAttribute($gitHubDriver, 'tags', [$identifier => $sha]);
+        $this->setAttribute($gitHubDriver, 'branches', ['test_master' => $sha]);
+
+        $data = $gitHubDriver->getComposerInformation($identifier);
+
+        $this->assertIsArray($data);
+        $this->assertSame('https://github.com/composer/packagist/tree/feature/3.2-foo', $data['support']['source']);
+    }
+
     public function testPublicRepositoryArchived(): void
     {
         $repoUrl = 'http://github.com/composer/packagist';
diff --git a/tests/Composer/Test/Repository/Vcs/GitLabDriverTest.php b/tests/Composer/Test/Repository/Vcs/GitLabDriverTest.php
index 2f9dae2b9..9d163f567 100644
--- a/tests/Composer/Test/Repository/Vcs/GitLabDriverTest.php
+++ b/tests/Composer/Test/Repository/Vcs/GitLabDriverTest.php
@@ -244,6 +244,22 @@ JSON;
         $this->assertEquals($url, $driver->getUrl());
     }
 
+    public function testInvalidSupportData(): void
+    {
+        $driver = $this->testInitialize($repoUrl = 'https://gitlab.com/mygroup/myproject', 'https://gitlab.com/api/v4/projects/mygroup%2Fmyproject');
+        $this->setAttribute($driver, 'branches', ['main' => 'SOMESHA']);
+        $this->setAttribute($driver, 'tags', []);
+
+        $this->httpDownloader->expects([
+            ['url' => 'https://gitlab.com/api/v4/projects/mygroup%2Fmyproject/repository/files/composer%2Ejson/raw?ref=SOMESHA', 'body' => '{"support": "'.$repoUrl.'" }'],
+        ], true);
+
+        $data = $driver->getComposerInformation('main');
+
+        $this->assertIsArray($data);
+        $this->assertSame('https://gitlab.com/mygroup/myproject/-/tree/main', $data['support']['source']);
+    }
+
     public function testGetDist(): void
     {
         $driver = $this->testInitialize('https://gitlab.com/mygroup/myproject', 'https://gitlab.com/api/v4/projects/mygroup%2Fmyproject');
@@ -631,4 +647,15 @@ JSON;
         $driver->initialize();
         $this->assertEquals('https://gitlab.com/mygroup/myproject.git', $driver->getRepositoryUrl(), 'Repository URL matches config request for http not git');
     }
+
+    /**
+     * @param object $object
+     * @param mixed  $value
+     */
+    protected function setAttribute($object, string $attribute, $value): void
+    {
+        $attr = new \ReflectionProperty($object, $attribute);
+        $attr->setAccessible(true);
+        $attr->setValue($object, $value);
+    }
 }