diff --git a/crypto/sessionkey.go b/crypto/sessionkey.go
index 1e48209d..a523fce8 100644
--- a/crypto/sessionkey.go
+++ b/crypto/sessionkey.go
@@ -409,6 +409,11 @@ func decryptStreamWithSessionKey(
 	// Decrypt data packet
 	switch p := p.(type) {
 	case *packet.SymmetricallyEncrypted, *packet.AEADEncrypted:
+		if symPacket, ok := p.(*packet.SymmetricallyEncrypted); ok {
+			if !symPacket.IntegrityProtected {
+				return nil, errors.New("gopenpgp: message is not authenticated")
+			}
+		}
 		dc, err := sk.GetCipherFunc()
 		if err != nil {
 			return nil, errors.Wrap(err, "gopenpgp: unable to decrypt with session key")
diff --git a/crypto/sessionkey_test.go b/crypto/sessionkey_test.go
index 09b28232..f66aa65d 100644
--- a/crypto/sessionkey_test.go
+++ b/crypto/sessionkey_test.go
@@ -408,3 +408,39 @@ func TestAEADDataPacketDecryption(t *testing.T) {
 
 	assert.Exactly(t, "hello world\n", decrypted.GetString())
 }
+
+func TestSEDDecryption(t *testing.T) {
+	pgpMessageData, err := ioutil.ReadFile("testdata/sed_message")
+	if err != nil {
+		t.Fatal("Expected no error when reading message data, got:", err)
+	}
+	pgpMessage, err := NewPGPMessageFromArmored(string(pgpMessageData))
+	if err != nil {
+		t.Fatal("Expected no error when creating message, got:", err)
+	}
+
+	split, err := pgpMessage.SplitMessage()
+	if err != nil {
+		t.Fatal("Expected no error when splitting, got:", err)
+	}
+
+	privateKey, err := NewKeyFromArmored(readTestFile("sed_key", false))
+	if err != nil {
+		t.Fatal("Expected no error when unarmoring key, got:", err)
+	}
+
+	kR, err := NewKeyRing(privateKey)
+	if err != nil {
+		t.Fatal("Expected no error when creating the keyring, got:", err)
+	}
+	defer kR.ClearPrivateParams()
+	sessionKey, err := kR.DecryptSessionKey(split.GetBinaryKeyPacket())
+	if err != nil {
+		t.Fatal("Expected no error when decrypting session key, got:", err)
+	}
+
+	_, err = sessionKey.Decrypt(split.GetBinaryDataPacket())
+	if err == nil {
+		t.Fatal("sed packets without authentication should not be allowed", err)
+	}
+}
diff --git a/crypto/testdata/sed_key b/crypto/testdata/sed_key
new file mode 100644
index 00000000..38a58591
--- /dev/null
+++ b/crypto/testdata/sed_key
@@ -0,0 +1,82 @@
+-----BEGIN PGP PRIVATE KEY BLOCK-----
+Comment: Bob's OpenPGP Transferable Secret Key
+
+lQVYBF2lnPIBDAC5cL9PQoQLTMuhjbYvb4Ncuuo0bfmgPRFywX53jPhoFf4Zg6mv
+/seOXpgecTdOcVttfzC8ycIKrt3aQTiwOG/ctaR4Bk/t6ayNFfdUNxHWk4WCKzdz
+/56fW2O0F23qIRd8UUJp5IIlN4RDdRCtdhVQIAuzvp2oVy/LaS2kxQoKvph/5pQ/
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+=miES
+-----END PGP PRIVATE KEY BLOCK-----
\ No newline at end of file
diff --git a/crypto/testdata/sed_message b/crypto/testdata/sed_message
new file mode 100644
index 00000000..bbadad28
--- /dev/null
+++ b/crypto/testdata/sed_message
@@ -0,0 +1,14 @@
+-----BEGIN PGP MESSAGE-----
+
+hQGMA3wvqk35PDeyAQwAyfOgW1muzY3NhAeShMCUzoAeAY6BGeJ2vCVZ1JCELVNk
+hxZIapaprHkmBHHlTOeS7r0YUhIoxgCbra1wh7o4qL7LGEh1EhuvXYi+2qXoCcCy
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+7FZr1phe3LZVUso6CUzJdyECJw==
+=meER
+-----END PGP MESSAGE-----
\ No newline at end of file