diff --git a/libavformat/libsrt.c b/libavformat/libsrt.c
index 1c34ec50b2..fd27e36b08 100644
--- a/libavformat/libsrt.c
+++ b/libavformat/libsrt.c
@@ -494,6 +494,7 @@ static int libsrt_open(URLContext *h, const char *uri, int flags)
             s->pbkeylen = strtol(buf, NULL, 10);
         }
         if (av_find_info_tag(buf, sizeof(buf), "passphrase", p)) {
+            av_freep(&s->passphrase);
             s->passphrase = av_strndup(buf, strlen(buf));
         }
         if (av_find_info_tag(buf, sizeof(buf), "mss", p)) {