diff --git a/libavformat/nistspheredec.c b/libavformat/nistspheredec.c
index c09df9ccc1..76f65ec6e0 100644
--- a/libavformat/nistspheredec.c
+++ b/libavformat/nistspheredec.c
@@ -108,8 +108,11 @@ static int nist_read_header(AVFormatContext *s)
             sscanf(buffer, "%*s %*s %"SCNd32, &st->codec->bits_per_coded_sample);
         } else {
             char key[32], value[32];
-            sscanf(buffer, "%31s %*s %31s", key, value);
-            av_dict_set(&s->metadata, key, value, AV_DICT_APPEND);
+            if (sscanf(buffer, "%31s %*s %31s", key, value) == 3) {
+                av_dict_set(&s->metadata, key, value, AV_DICT_APPEND);
+            } else {
+                av_log(s, AV_LOG_ERROR, "Failed to parse '%s' as metadata\n", buffer);
+            }
         }
     }