diff --git a/ext/srtp/gstsrtp.c b/ext/srtp/gstsrtp.c
index 30f765c94b..c108de2ccd 100644
--- a/ext/srtp/gstsrtp.c
+++ b/ext/srtp/gstsrtp.c
@@ -96,6 +96,8 @@ enum_nick_from_value (GType enum_gtype, gint value)
     return NULL;
 
   enum_value = g_enum_get_value (enum_class, value);
+  if (!enum_value)
+    return NULL;
   nick = enum_value->value_nick;
   g_type_class_unref (enum_class);
 
@@ -111,9 +113,11 @@ enum_value_from_nick (GType enum_gtype, const gchar * nick)
   gint value;
 
   if (!enum_gtype)
-    return 0;
+    return -1;
 
   enum_value = g_enum_get_value_by_nick (enum_class, nick);
+  if (!enum_value)
+    return -1;
   value = enum_value->value;
   g_type_class_unref (enum_class);
 
diff --git a/ext/srtp/gstsrtpdec.c b/ext/srtp/gstsrtpdec.c
index e38dc3ea35..e30d28a915 100644
--- a/ext/srtp/gstsrtpdec.c
+++ b/ext/srtp/gstsrtpdec.c
@@ -410,6 +410,13 @@ get_stream_from_caps (GstSrtpDec * filter, GstCaps * caps, guint32 ssrc)
       rtcp_cipher);
   stream->rtcp_auth = enum_value_from_nick (GST_TYPE_SRTP_AUTH_TYPE, rtcp_auth);
 
+  if (stream->rtp_cipher == -1 || stream->rtp_auth == -1 ||
+      stream->rtcp_cipher == -1 || stream->rtcp_auth == -1) {
+    GST_WARNING_OBJECT (filter, "Invalid caps for stream,"
+        " unknown cipher or auth type");
+    goto error;
+  }
+
   if (stream->rtcp_cipher != NULL_CIPHER && stream->rtcp_auth == NULL_AUTH) {
     GST_WARNING_OBJECT (filter,
         "Cannot have SRTP NULL authentication with a not-NULL encryption"