diff --git a/src/core/ngx_crypt.c b/src/core/ngx_crypt.c
index 629d160..e2376c6 100644
--- a/src/core/ngx_crypt.c
+++ b/src/core/ngx_crypt.c
@@ -137,7 +137,7 @@
 
     /* output */
 
-    *encrypted = ngx_pnalloc(pool, sizeof("$apr1$") - 1 + saltlen + 16 + 1);
+    *encrypted = ngx_pnalloc(pool, sizeof("$apr1$") - 1 + saltlen + 1 + 22 + 1);
     if (*encrypted == NULL) {
         return NGX_ERROR;
     }