diff --git a/src/c-wrapper/api/c-content.cpp b/src/c-wrapper/api/c-content.cpp
index c0d939126..0671204ff 100644
--- a/src/c-wrapper/api/c-content.cpp
+++ b/src/c-wrapper/api/c-content.cpp
@@ -40,7 +40,6 @@ L_DECLARE_C_CLONABLE_OBJECT_IMPL_WITH_XTORS(Content,
 	void *cryptoContext; // Used to encrypt file for RCS file transfer.
 
 	mutable size_t size;
-	mutable char *key;
 
 	struct Cache {
 		string name;
@@ -213,15 +212,12 @@ const char *linphone_content_get_custom_header (const LinphoneContent *content,
 }
 
 const char *linphone_content_get_key (const LinphoneContent *content) {
-	if (content->key) bctbx_free(content->key);
-
 	const LinphonePrivate::Content *c = L_GET_CPP_PTR_FROM_C_OBJECT(content);
 	if (c->isFileTransfer()) {
 		const LinphonePrivate::FileTransferContent *ftc = static_cast<const LinphonePrivate::FileTransferContent *>(c);
-		content->key = bctbx_strdup(ftc->getFileKeyAsString());
+		return ftc->getFileKey().data();
 	}
-
-	return content->key;
+	return nullptr;
 }
 
 size_t linphone_content_get_key_size (const LinphoneContent *content) {
diff --git a/src/chat/modifier/file-transfer-chat-message-modifier.cpp b/src/chat/modifier/file-transfer-chat-message-modifier.cpp
index ad17cfff7..f73581c6b 100644
--- a/src/chat/modifier/file-transfer-chat-message-modifier.cpp
+++ b/src/chat/modifier/file-transfer-chat-message-modifier.cpp
@@ -318,9 +318,9 @@ void FileTransferChatMessageModifier::processResponseFromPostFile (const belle_h
 			const char *body = belle_sip_message_get_body((belle_sip_message_t *)event->response);
 			if (body && strlen(body) > 0) {
 				// if we have an encryption key for the file, we must insert it into the msg and restore the correct filename
-				const char *content_key = fileTransferContent->getFileKeyAsString();
-				size_t content_key_size = fileTransferContent->getFileKey().size();
-				if (content_key_size > 0) {
+				const unsigned char *contentKey = reinterpret_cast<const unsigned char *>(fileTransferContent->getFileKey().data());
+				size_t contentKeySize = fileTransferContent->getFileKeySize();
+				if (contentKeySize > 0) {
 					// parse the msg body
 					xmlDocPtr xmlMessageBody = xmlParseDoc((const xmlChar *)body);
 
@@ -337,11 +337,11 @@ void FileTransferChatMessageModifier::processResponseFromPostFile (const belle_h
 									xmlNodePtr fileInfoNodeChildren = cur->xmlChildrenNode;
 									// convert key to base64
 									size_t b64Size;
-									bctbx_base64_encode(nullptr, &b64Size, (unsigned char *)content_key, content_key_size);
+									bctbx_base64_encode(nullptr, &b64Size, contentKey, contentKeySize);
 									unsigned char *keyb64 = (unsigned char *)ms_malloc0(b64Size + 1);
 									int xmlStringLength;
 
-									bctbx_base64_encode(keyb64, &b64Size, (unsigned char *)content_key, content_key_size);
+									bctbx_base64_encode(keyb64, &b64Size, contentKey, contentKeySize);
 									keyb64[b64Size] = '\0'; // libxml need a null terminated string
 
 									// add the node containing the key to the file-info node
diff --git a/src/content/file-transfer-content.cpp b/src/content/file-transfer-content.cpp
index 2b8e228bb..8bf22f7a0 100644
--- a/src/content/file-transfer-content.cpp
+++ b/src/content/file-transfer-content.cpp
@@ -164,11 +164,6 @@ const vector<char> &FileTransferContent::getFileKey () const {
 	return d->fileKey;
 }
 
-const char *FileTransferContent::getFileKeyAsString() const {
-	L_D();
-	return d->fileKey.data();
-}
-
 size_t FileTransferContent::getFileKeySize() const {
 	L_D();
 	return d->fileKey.size();
diff --git a/src/content/file-transfer-content.h b/src/content/file-transfer-content.h
index 1904e11c5..4ae07867b 100644
--- a/src/content/file-transfer-content.h
+++ b/src/content/file-transfer-content.h
@@ -59,7 +59,6 @@ public:
 
 	void setFileKey (const char *key, size_t size);
 	const std::vector<char> &getFileKey () const;
-	const char *getFileKeyAsString () const;
 	size_t getFileKeySize() const;
 
 	bool isFile () const override;