diff --git a/programs/fuzz/fuzz_pubkey.c b/programs/fuzz/fuzz_pubkey.c
index df42f7d..3a59125 100644
--- a/programs/fuzz/fuzz_pubkey.c
+++ b/programs/fuzz/fuzz_pubkey.c
@@ -20,7 +20,9 @@
             mbedtls_mpi_init( &DQ ); mbedtls_mpi_init( &QP );
 
             rsa = mbedtls_pk_rsa( pk );
-            ret = mbedtls_rsa_export( rsa, &N, &P, &Q, &D, &E );
+            if ( mbedtls_rsa_export( rsa, &N, &P, &Q, &D, &E ) != 0 ) {
+                abort();
+            }
             ret = mbedtls_rsa_export_crt( rsa, &DP, &DQ, &QP );
 
             mbedtls_mpi_free( &N ); mbedtls_mpi_free( &P ); mbedtls_mpi_free( &Q );