diff --git a/composer.json b/composer.json
index 45bb0617e941c5f202a1a5b4c3da077c28d0fc9c..030469ee7fc4aca47680d5c8c31186dd56066d1f 100644
--- a/composer.json
+++ b/composer.json
@@ -92,6 +92,7 @@
 	},
 	"conflict": {
 		"hoa/core": "*",
+		"guzzlehttp/guzzle": ">= 6.5.0",
 		"phpdocumentor/reflection-docblock": ">= 4.3.2"
 	},
 	"provide": {
diff --git a/composer.lock b/composer.lock
index 8f6404b857fbadfbe4183a9be2183484b4c21348..ef3b68614c99a06b44bec39b790e5a74ee4851ed 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "849495c5f9338523ee9caeecb03741fc",
+    "content-hash": "49295a72bf4b2cda613861fea81568b3",
     "packages": [
         {
             "name": "cogpowered/finediff",
diff --git a/typo3/sysext/core/composer.json b/typo3/sysext/core/composer.json
index c19e577344cc7cd60b2e7368f45d229ea9d5f51e..11f955fa5f3ae78d5f0bff8e58f207927df3c80e 100644
--- a/typo3/sysext/core/composer.json
+++ b/typo3/sysext/core/composer.json
@@ -70,6 +70,7 @@
 	},
 	"conflict": {
 		"hoa/core": "*",
+		"guzzlehttp/guzzle": ">= 6.5.0",
 		"typo3/cms": "*"
 	},
 	"replace": {