diff --git a/ctaocrypt/benchmark/benchmark.c b/ctaocrypt/benchmark/benchmark.c
index 00ac9d220..b2517f084 100644
--- a/ctaocrypt/benchmark/benchmark.c
+++ b/ctaocrypt/benchmark/benchmark.c
@@ -1061,9 +1061,9 @@ void bench_ntruKeyGen(void)
     double start, total, each, milliEach;
     int    i;
 
-    byte   public_key[5951]; /* 2048 key equivalent to rsa */
+    byte   public_key[557]; /* 2048 key equivalent to rsa */
     word16 public_key_len = sizeof(public_key);
-    byte   private_key[5951];
+    byte   private_key[607];
     word16 private_key_len = sizeof(private_key);
 
     DRBG_HANDLE drbg;