diff --git a/docs/HACKING.CRYPTO b/docs/HACKING.CRYPTO
index b78a0148..ea2530bb 100644
--- a/docs/HACKING.CRYPTO
+++ b/docs/HACKING.CRYPTO
@@ -897,5 +897,6 @@ In example, this is needed to preset unused structure slacks on platforms
 requiring it.
 If this is not needed, it should be defined as an empty macro.
 
-void _libssh2_random(unsigned char *buf, int len);
+int _libssh2_random(unsigned char *buf, int len);
 Store len random bytes at buf.
+Returns 0 if OK, else -1.
diff --git a/include/libssh2.h b/include/libssh2.h
index 4931a2af..f17b502e 100644
--- a/include/libssh2.h
+++ b/include/libssh2.h
@@ -505,6 +505,7 @@ typedef struct _LIBSSH2_POLLFD {
 #define LIBSSH2_ERROR_KNOWN_HOSTS               -46
 #define LIBSSH2_ERROR_CHANNEL_WINDOW_FULL       -47
 #define LIBSSH2_ERROR_KEYFILE_AUTH_FAILED       -48
+#define LIBSSH2_ERROR_RANDGEN                   -49
 
 /* this is a define to provide the old (<= 1.2.7) name */
 #define LIBSSH2_ERROR_BANNER_NONE LIBSSH2_ERROR_BANNER_RECV
diff --git a/src/channel.c b/src/channel.c
index 55a16e9f..78ed40e8 100644
--- a/src/channel.c
+++ b/src/channel.c
@@ -1338,7 +1338,11 @@ channel_x11_req(LIBSSH2_CHANNEL *channel, int single_connection,
                border */
             unsigned char buffer[(LIBSSH2_X11_RANDOM_COOKIE_LEN / 2) + 1];
 
-            _libssh2_random(buffer, LIBSSH2_X11_RANDOM_COOKIE_LEN / 2);
+            if(_libssh2_random(buffer, LIBSSH2_X11_RANDOM_COOKIE_LEN / 2)) {
+                return _libssh2_error(session, LIBSSH2_ERROR_RANDGEN,
+                                      "Unable to get random bytes "
+                                      "for x11-req cookie");
+            }
             for(i = 0; i < (LIBSSH2_X11_RANDOM_COOKIE_LEN / 2); i++) {
                 snprintf((char *)&s[i*2], 3, "%02X", buffer[i]);
             }
diff --git a/src/kex.c b/src/kex.c
index ed00c6a3..9f3ef799 100644
--- a/src/kex.c
+++ b/src/kex.c
@@ -3176,7 +3176,11 @@ static int kexinit(LIBSSH2_SESSION * session)
 
         *(s++) = SSH_MSG_KEXINIT;
 
-        _libssh2_random(s, 16);
+        if(_libssh2_random(s, 16)) {
+            return _libssh2_error(session, LIBSSH2_ERROR_RANDGEN,
+                                  "Unable to get random bytes "
+                                  "for KEXINIT cookie");
+        }
         s += 16;
 
         /* Ennumerating through these lists twice is probably (certainly?)
diff --git a/src/libgcrypt.h b/src/libgcrypt.h
index 92b48b88..298c65ed 100644
--- a/src/libgcrypt.h
+++ b/src/libgcrypt.h
@@ -68,7 +68,7 @@
 #define EC_MAX_POINT_LEN ((528 * 2 / 8) + 1)
 
 #define _libssh2_random(buf, len)                \
-  (gcry_randomize ((buf), (len), GCRY_STRONG_RANDOM), 1)
+  (gcry_randomize ((buf), (len), GCRY_STRONG_RANDOM), 0)
 
 #define libssh2_prepare_iovec(vec, len)  /* Empty. */
 
diff --git a/src/openssl.h b/src/openssl.h
index 66ff1b26..658b040d 100644
--- a/src/openssl.h
+++ b/src/openssl.h
@@ -137,7 +137,7 @@
 
 #define EC_MAX_POINT_LEN ((528 * 2 / 8) + 1)
 
-#define _libssh2_random(buf, len) RAND_bytes ((buf), (len))
+#define _libssh2_random(buf, len) (RAND_bytes((buf), (len)) == 1 ? 0 : -1)
 
 #define libssh2_prepare_iovec(vec, len)  /* Empty. */
 
diff --git a/src/os400qc3.c b/src/os400qc3.c
index bf5acdaf..f05bfabf 100644
--- a/src/os400qc3.c
+++ b/src/os400qc3.c
@@ -884,11 +884,14 @@ _libssh2_bn_from_bn(_libssh2_bn *to, _libssh2_bn *from)
     return 0;
 }
 
-void
+int
 _libssh2_random(unsigned char *buf, int len)
 {
     Qc3GenPRNs(buf, len,
         Qc3PRN_TYPE_NORMAL, Qc3PRN_NO_PARITY, (char *) &ecnull);
+    /* FIXME: any error is silently discarded! But Qc3GenPRNs could fail,
+       including if "The system seed digest is not ready" dixit IBM doc. */
+    return 0;
 }
 
 
diff --git a/src/os400qc3.h b/src/os400qc3.h
index f0d2ea50..e3602d9f 100644
--- a/src/os400qc3.h
+++ b/src/os400qc3.h
@@ -360,7 +360,7 @@ extern int      _libssh2_bn_from_bin(_libssh2_bn *bn, int len,
                                      const unsigned char *v);
 extern int      _libssh2_bn_set_word(_libssh2_bn *bn, unsigned long val);
 extern int      _libssh2_bn_to_bin(_libssh2_bn *bn, unsigned char *val);
-extern void     _libssh2_random(unsigned char *buf, int len);
+extern int      _libssh2_random(unsigned char *buf, int len);
 extern void     _libssh2_os400qc3_crypto_dtor(_libssh2_os400qc3_crypto_ctx *x);
 extern int      libssh2_os400qc3_hash_init(Qc3_Format_ALGD0100_T *x,
                                            unsigned int algo);
diff --git a/src/transport.c b/src/transport.c
index 1a997279..17af3e4d 100644
--- a/src/transport.c
+++ b/src/transport.c
@@ -862,7 +862,10 @@ int _libssh2_transport_send(LIBSSH2_SESSION *session,
     p->outbuf[4] = (unsigned char)padding_length;
 
     /* fill the padding area with random junk */
-    _libssh2_random(p->outbuf + 5 + data_len, padding_length);
+    if(_libssh2_random(p->outbuf + 5 + data_len, padding_length)) {
+        return _libssh2_error(session, LIBSSH2_ERROR_RANDGEN,
+                              "Unable to get random bytes for packet padding");
+    }
 
     if(encrypted) {
         size_t i;