diff --git a/packet_unpacker.go b/packet_unpacker.go
index ca0a8cdc..13c773c7 100644
--- a/packet_unpacker.go
+++ b/packet_unpacker.go
@@ -22,12 +22,14 @@ type packetUnpacker struct {
 }
 
 func (u *packetUnpacker) Unpack(publicHeaderBinary []byte, hdr *PublicHeader, data []byte) (*unpackedPacket, error) {
-	data, err := u.aead.Open(data[:0], data, hdr.PacketNumber, publicHeaderBinary)
+	buf := getPacketBuffer()
+	defer putPacketBuffer(buf)
+	decrypted, err := u.aead.Open(buf, data, hdr.PacketNumber, publicHeaderBinary)
 	if err != nil {
 		// Wrap err in quicError so that public reset is sent by session
 		return nil, qerr.Error(qerr.DecryptionFailure, err.Error())
 	}
-	r := bytes.NewReader(data)
+	r := bytes.NewReader(decrypted)
 
 	// read private flag byte, for QUIC Version < 34
 	var entropyBit bool