diff --git a/lib/private/Http/Client/DnsPinMiddleware.php b/lib/private/Http/Client/DnsPinMiddleware.php
index b031f3f32366f..cb868aa7cb51f 100644
--- a/lib/private/Http/Client/DnsPinMiddleware.php
+++ b/lib/private/Http/Client/DnsPinMiddleware.php
@@ -25,6 +25,17 @@ public function __construct(
 	) {
 	}
 
+	/**
+	 * DNS lookups must end with a dot to be marked as
+	 * FQDN. Otherwise, a record without answer may trigger
+	 * a lookup on the local domain name. See GitHub
+	 * issue #56489 for details.
+	 */
+	private function enforceFqdn(string $hostname): string {
+		$trimmedHostname = rtrim($hostname, '.');
+		return "$trimmedHostname.";
+	}
+
 	/**
 	 * Fetch soa record for a target
 	 */
@@ -35,7 +46,7 @@ private function soaRecord(string $target): ?array {
 		$second = array_pop($labels);
 
 		$hostname = $second . '.' . $top;
-		$responses = $this->dnsGetRecord($hostname, DNS_SOA);
+		$responses = $this->dnsGetRecord($this->enforceFqdn($hostname), DNS_SOA);
 
 		if ($responses === false || count($responses) === 0) {
 			return null;
@@ -68,7 +79,7 @@ private function dnsResolve(string $target, int $recursionCount) : array {
 				continue;
 			}
 
-			$dnsResponses = $this->dnsGetRecord($target, $dnsType);
+			$dnsResponses = $this->dnsGetRecord($this->enforceFqdn($target), $dnsType);
 			if ($dnsResponses !== false && count($dnsResponses) > 0) {
 				foreach ($dnsResponses as $dnsResponse) {
 					if (isset($dnsResponse['ip'])) {
diff --git a/tests/lib/Http/Client/DnsPinMiddlewareTest.php b/tests/lib/Http/Client/DnsPinMiddlewareTest.php
index 790206a94220a..2699e609c5e5a 100644
--- a/tests/lib/Http/Client/DnsPinMiddlewareTest.php
+++ b/tests/lib/Http/Client/DnsPinMiddlewareTest.php
@@ -61,7 +61,7 @@ static function (RequestInterface $request, array $options) {
 			->method('dnsGetRecord')
 			->willReturnCallback(function (string $hostname, int $type) {
 				// example.com SOA
-				if ($hostname === 'example.com') {
+				if ($hostname === 'example.com.') {
 					return match ($type) {
 						DNS_SOA => [
 							[
@@ -76,7 +76,7 @@ static function (RequestInterface $request, array $options) {
 				}
 
 				// example.com A, AAAA, CNAME
-				if ($hostname === 'www.example.com') {
+				if ($hostname === 'www.example.com.') {
 					return match ($type) {
 						DNS_A => [],
 						DNS_AAAA => [],
@@ -93,7 +93,7 @@ static function (RequestInterface $request, array $options) {
 				}
 
 				// example.net SOA
-				if ($hostname === 'example.net') {
+				if ($hostname === 'example.net.') {
 					return match ($type) {
 						DNS_SOA => [
 							[
@@ -108,7 +108,7 @@ static function (RequestInterface $request, array $options) {
 				}
 
 				// example.net A, AAAA, CNAME
-				if ($hostname === 'www.example.net') {
+				if ($hostname === 'www.example.net.') {
 					return match ($type) {
 						DNS_A => [
 							[
@@ -154,7 +154,7 @@ static function (RequestInterface $request, array $options) {
 			->method('dnsGetRecord')
 			->willReturnCallback(function (string $hostname, int $type) {
 				// example.com SOA
-				if ($hostname === 'example.com') {
+				if ($hostname === 'example.com.') {
 					return match ($type) {
 						DNS_SOA => [
 							[
@@ -169,7 +169,7 @@ static function (RequestInterface $request, array $options) {
 				}
 
 				// example.com A, AAAA, CNAME
-				if ($hostname === 'www.example.com') {
+				if ($hostname === 'www.example.com.') {
 					return match ($type) {
 						DNS_A => [],
 						DNS_AAAA => [],
@@ -186,7 +186,7 @@ static function (RequestInterface $request, array $options) {
 				}
 
 				// example.net SOA
-				if ($hostname === 'example.net') {
+				if ($hostname === 'example.net.') {
 					return match ($type) {
 						DNS_SOA => [
 							[
@@ -201,7 +201,7 @@ static function (RequestInterface $request, array $options) {
 				}
 
 				// example.net A, AAAA, CNAME
-				if ($hostname === 'www.example.net') {
+				if ($hostname === 'www.example.net.') {
 					return match ($type) {
 						DNS_A => [
 							[
@@ -378,7 +378,7 @@ static function (RequestInterface $request, array $options): void {
 			->method('dnsGetRecord')
 			->willReturnCallback(function (string $hostname, int $type) {
 				// example.com SOA
-				if ($hostname === 'example.com') {
+				if ($hostname === 'example.com.') {
 					return match ($type) {
 						DNS_SOA => [
 							[
@@ -393,7 +393,7 @@ static function (RequestInterface $request, array $options): void {
 				}
 
 				// example.com A, AAAA, CNAME
-				if ($hostname === 'www.example.com') {
+				if ($hostname === 'www.example.com.') {
 					return match ($type) {
 						DNS_A => [],
 						DNS_AAAA => [],
@@ -410,7 +410,7 @@ static function (RequestInterface $request, array $options): void {
 				}
 
 				// example.net SOA
-				if ($hostname === 'example.net') {
+				if ($hostname === 'example.net.') {
 					return match ($type) {
 						DNS_SOA => [
 							[
@@ -425,7 +425,7 @@ static function (RequestInterface $request, array $options): void {
 				}
 
 				// example.net A, AAAA, CNAME
-				if ($hostname === 'www.example.net') {
+				if ($hostname === 'www.example.net.') {
 					return match ($type) {
 						DNS_A => [
 							[
@@ -496,7 +496,7 @@ static function (RequestInterface $request, array $options): void {
 				$dnsQueries[] = $hostname . $type;
 
 				// example.com SOA
-				if ($hostname === 'example.com') {
+				if ($hostname === 'example.com.') {
 					return match ($type) {
 						DNS_SOA => [
 							[
@@ -511,7 +511,7 @@ static function (RequestInterface $request, array $options): void {
 				}
 
 				// example.net A, AAAA, CNAME
-				if ($hostname === 'subsubdomain.subdomain.example.com') {
+				if ($hostname === 'subsubdomain.subdomain.example.com.') {
 					return match ($type) {
 						DNS_A => [
 							[
@@ -540,10 +540,10 @@ static function (RequestInterface $request, array $options): void {
 		);
 
 		$this->assertCount(3, $dnsQueries);
-		$this->assertContains('example.com' . DNS_SOA, $dnsQueries);
-		$this->assertContains('subsubdomain.subdomain.example.com' . DNS_A, $dnsQueries);
-		$this->assertContains('subsubdomain.subdomain.example.com' . DNS_AAAA, $dnsQueries);
+		$this->assertContains('example.com.' . DNS_SOA, $dnsQueries);
+		$this->assertContains('subsubdomain.subdomain.example.com.' . DNS_A, $dnsQueries);
+		$this->assertContains('subsubdomain.subdomain.example.com.' . DNS_AAAA, $dnsQueries);
 		// CNAME should not be queried if A or AAAA succeeded already
-		$this->assertNotContains('subsubdomain.subdomain.example.com' . DNS_CNAME, $dnsQueries);
+		$this->assertNotContains('subsubdomain.subdomain.example.com.' . DNS_CNAME, $dnsQueries);
 	}
 }