diff --git a/libavcodec/xxan.c b/libavcodec/xxan.c
index 865dfa8f87..1dd46b36eb 100644
--- a/libavcodec/xxan.c
+++ b/libavcodec/xxan.c
@@ -443,5 +443,5 @@ AVCodec ff_xan_wc4_decoder = {
     .close          = xan_decode_end,
     .decode         = xan_decode_frame,
     .capabilities   = AV_CODEC_CAP_DR1,
-    .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP,
+    .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP | FF_CODEC_CAP_INIT_THREADSAFE,
 };