diff --git a/config.c b/config.c
index 2f12e201..50306b9d 100644
--- a/config.c
+++ b/config.c
@@ -614,6 +614,7 @@ value_to_enum(struct context *ctx, const char **value_map, int *res)
         valid_values[idx - 2] = '\0';
 
     LOG_CONTEXTUAL_ERR("not one of %s", valid_values);
+    free(valid_values);
     *res = -1;
     return false;
 }