diff --git a/src/enc/vp8l_enc.c b/src/enc/vp8l_enc.c
index 0b07e529..cb5549af 100644
--- a/src/enc/vp8l_enc.c
+++ b/src/enc/vp8l_enc.c
@@ -259,6 +259,7 @@ static int PaletteSortModifiedZeng(
     return 0;
   }
   if (!CoOccurrenceBuild(pic, palette_sorted, num_colors, cooccurrence)) {
+    WebPSafeFree(cooccurrence);
     return 0;
   }