diff --git a/test/default/box_easy2.c b/test/default/box_easy2.c
index 8848fea1..71fe5ead 100644
--- a/test/default/box_easy2.c
+++ b/test/default/box_easy2.c
@@ -2,10 +2,6 @@
 #define TEST_NAME "box_easy2"
 #include "cmptest.h"
 
-static unsigned char m[10000];
-static unsigned char m2[10000];
-static unsigned char c[crypto_box_MACBYTES + 10000];
-
 int main(void)
 {
     unsigned char *alicepk;
@@ -16,10 +12,21 @@ int main(void)
     unsigned char *nonce;
     unsigned char *k1;
     unsigned char *k2;
+    unsigned char *m;
+    unsigned char *m2;
+    unsigned char *c;
     size_t         mlen;
     size_t         i;
+    size_t         m_size;
+    size_t         m2_size;
+    size_t         c_size;
     int            ret;
 
+    m2_size = m_size = 1U + randombytes_uniform(10000);
+    c_size = crypto_box_MACBYTES + m_size;
+    m = (unsigned char *) sodium_malloc(m_size);
+    m2 = (unsigned char *) sodium_malloc(m2_size);
+    c = (unsigned char *) sodium_malloc(c_size);
     alicepk = (unsigned char *) sodium_malloc(crypto_box_PUBLICKEYBYTES);
     alicesk = (unsigned char *) sodium_malloc(crypto_box_SECRETKEYBYTES);
     bobpk = (unsigned char *) sodium_malloc(crypto_box_PUBLICKEYBYTES);
@@ -30,7 +37,7 @@ int main(void)
     k2 = (unsigned char *) sodium_malloc(crypto_box_BEFORENMBYTES);
     crypto_box_keypair(alicepk, alicesk);
     crypto_box_keypair(bobpk, bobsk);
-    mlen = (size_t) randombytes_uniform((uint32_t)sizeof m);
+    mlen = (size_t) randombytes_uniform((uint32_t) m_size) + 1U;
     randombytes_buf(m, mlen);
     randombytes_buf(nonce, crypto_box_NONCEBYTES);
     ret = crypto_box_easy(c, m, mlen, nonce, bobpk, alicesk);
@@ -50,7 +57,6 @@ int main(void)
             return 1;
         }
     }
-
     memcpy(c, m, mlen);
     ret = crypto_box_easy(c, c, (unsigned long long) mlen, nonce, bobpk, alicesk);
     assert(ret == 0);
@@ -67,7 +73,7 @@ int main(void)
     ret = crypto_box_beforenm(k2, bobpk, alicesk);
     assert(ret == 0);
 
-    memset(m2, 0, sizeof m2);
+    memset(m2, 0, m2_size);
 
     if (crypto_box_easy_afternm(c, m, SIZE_MAX - 1U, nonce, k1) == 0) {
         printf("crypto_box_easy_afternm() with a short ciphertext should have failed\n");
@@ -83,7 +89,7 @@ int main(void)
                                      nonce, k2) == 0) {
         printf("crypto_box_open_easy_afternm() with a huge ciphertext should have failed\n");
     }
-    memset(m2, 0, sizeof m2);
+    memset(m2, 0, m2_size);
     ret = crypto_box_detached(c, mac, m, (unsigned long long) mlen,
                               nonce, alicepk, bobsk);
     assert(ret == 0);
@@ -93,7 +99,7 @@ int main(void)
     }
     printf("%d\n", memcmp(m, m2, mlen));
 
-    memset(m2, 0, sizeof m2);
+    memset(m2, 0, m2_size);
     crypto_box_detached_afternm(c, mac, m, (unsigned long long) mlen,
                                 nonce, k1);
     if (crypto_box_open_detached_afternm(m2, c, mac, (unsigned long long) mlen,
@@ -110,6 +116,9 @@ int main(void)
     sodium_free(nonce);
     sodium_free(k1);
     sodium_free(k2);
+    sodium_free(m);
+    sodium_free(m2);
+    sodium_free(c);
     printf("OK\n");
 
     return 0;