diff --git a/ctaocrypt/src/asn.c b/ctaocrypt/src/asn.c
index 7a1d0f363..673d89bf2 100644
--- a/ctaocrypt/src/asn.c
+++ b/ctaocrypt/src/asn.c
@@ -1359,7 +1359,7 @@ static int GetCertHeader(DecodedCert* cert)
 
     len = mp_unsigned_bin_size(&mpi);
     if (len < (int)sizeof(serialTmp)) {
-        if (mp_to_unsigned_bin(&mpi, serialTmp) == MP_OKAY) {
+        if ( (ret = mp_to_unsigned_bin(&mpi, serialTmp)) == MP_OKAY) {
             if (len > EXTERNAL_SERIAL_SIZE)
                 len = EXTERNAL_SERIAL_SIZE;
             XMEMCPY(cert->serial, serialTmp, len);
diff --git a/ctaocrypt/src/ecc.c b/ctaocrypt/src/ecc.c
index 9b6cb1aa8..209b41ae5 100644
--- a/ctaocrypt/src/ecc.c
+++ b/ctaocrypt/src/ecc.c
@@ -1582,20 +1582,23 @@ static int ecc_mul2add(ecc_point* A, mp_int* kA,
 
   if (err == MP_OKAY) {
     /* extract and justify kA */
-    mp_to_unsigned_bin(kA, (len - lenA) + tA);
+    err = mp_to_unsigned_bin(kA, (len - lenA) + tA);
 
     /* extract and justify kB */
-    mp_to_unsigned_bin(kB, (len - lenB) + tB);
+    if (err == MP_OKAY)
+        err = mp_to_unsigned_bin(kB, (len - lenB) + tB);
 
     /* allocate the table */
-    for (x = 0; x < 16; x++) {
-        precomp[x] = ecc_new_point();
-        if (precomp[x] == NULL) {
-            for (y = 0; y < x; ++y) {
-                ecc_del_point(precomp[y]);
+    if (err == MP_OKAY) {
+        for (x = 0; x < 16; x++) {
+            precomp[x] = ecc_new_point();
+            if (precomp[x] == NULL) {
+                for (y = 0; y < x; ++y) {
+                    ecc_del_point(precomp[y]);
+                }
+                err = GEN_MEM_ERR;
+                break;
             }
-            err = GEN_MEM_ERR;
-            break;
         }
     }
   }
@@ -1943,6 +1946,7 @@ int ecc_export_x963(ecc_key* key, byte* out, word32* outLen)
 {
    byte   buf[ECC_BUFSIZE];
    word32 numlen;
+   int    ret = MP_OKAY;
 
    if (key == NULL || out == NULL || outLen == NULL)
        return ECC_BAD_ARG_E;
@@ -1962,14 +1966,18 @@ int ecc_export_x963(ecc_key* key, byte* out, word32* outLen)
 
    /* pad and store x */
    XMEMSET(buf, 0, sizeof(buf));
-   mp_to_unsigned_bin(&key->pubkey.x,
+   ret = mp_to_unsigned_bin(&key->pubkey.x,
                       buf + (numlen - mp_unsigned_bin_size(&key->pubkey.x)));
+   if (ret != MP_OKAY)
+       return ret;
    XMEMCPY(out+1, buf, numlen);
 
    /* pad and store y */
    XMEMSET(buf, 0, sizeof(buf));
-   mp_to_unsigned_bin(&key->pubkey.y,
+   ret = mp_to_unsigned_bin(&key->pubkey.y,
                       buf + (numlen - mp_unsigned_bin_size(&key->pubkey.y)));
+   if (ret != MP_OKAY)
+       return ret;
    XMEMCPY(out+1+numlen, buf, numlen);
 
    *outLen = 1 + 2*numlen;
diff --git a/ctaocrypt/src/pwdbased.c b/ctaocrypt/src/pwdbased.c
index 8a7fc1478..3f330ef4d 100644
--- a/ctaocrypt/src/pwdbased.c
+++ b/ctaocrypt/src/pwdbased.c
@@ -325,15 +325,15 @@ int PKCS12_PBKDF(byte* output, const byte* passwd, int passLen,const byte* salt,
                 if (outSz > (int)v) {
                     /* take off MSB */
                     byte  tmp[129];
-                    mp_to_unsigned_bin(&res, tmp);
+                    ret = mp_to_unsigned_bin(&res, tmp);
                     XMEMCPY(I + i, tmp + 1, v);
                 }
                 else if (outSz < (int)v) {
                     XMEMSET(I + i, 0, v - outSz);
-                    mp_to_unsigned_bin(&res, I + i + v - outSz);
+                    ret = mp_to_unsigned_bin(&res, I + i + v - outSz);
                 }
                 else
-                    mp_to_unsigned_bin(&res, I + i);
+                    ret = mp_to_unsigned_bin(&res, I + i);
             }
 
             mp_clear(&i1);