diff --git a/crypto/evp/evp_enc.c b/crypto/evp/evp_enc.c
index 1eb894b87fb74ca42fc37b32878d84efa4f2516e..0ccea3599ecbc7916d8e066e6e9761185e89aea2 100644
--- a/crypto/evp/evp_enc.c
+++ b/crypto/evp/evp_enc.c
@@ -957,9 +957,11 @@ int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr)
 
 int EVP_CIPHER_CTX_rand_key(EVP_CIPHER_CTX *ctx, unsigned char *key)
 {
+    int kl;
     if (ctx->cipher->flags & EVP_CIPH_RAND_KEY)
         return EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_RAND_KEY, 0, key);
-    if (RAND_priv_bytes(key, EVP_CIPHER_CTX_key_length(ctx)) <= 0)
+    kl = EVP_CIPHER_CTX_key_length(ctx);
+    if (kl <= 0 || RAND_priv_bytes(key, kl) <= 0)
         return 0;
     return 1;
 }