1 files changed, 6 insertions, 0 deletions
diff --git a/crypto/pem/pem_pkey.c b/crypto/pem/pem_pkey.c
index e58cdf4a3e..7bd9aa097e 100644
--- a/crypto/pem/pem_pkey.c
+++ b/crypto/pem/pem_pkey.c
@@ -108,6 +108,12 @@ int PEM_write_bio_PrivateKey_traditional(BIO *bp, EVP_PKEY *x,
                                          pem_password_cb *cb, void *u)
 {
     char pem_str[80];
+
+    if (x->ameth == NULL || x->ameth->old_priv_encode == NULL) {
+        PEMerr(PEM_F_PEM_WRITE_BIO_PRIVATEKEY_TRADITIONAL,
+               PEM_R_UNSUPPORTED_PUBLIC_KEY_TYPE);
+        return 0;
+    }
     BIO_snprintf(pem_str, 80, "%s PRIVATE KEY", x->ameth->pem_str);
     return PEM_ASN1_write_bio((i2d_of_void *)i2d_PrivateKey,
                               pem_str, bp, x, enc, kstr, klen, cb, u);