diff --git a/library/error.c b/library/error.c
index 701c792..d7e85a5 100644
--- a/library/error.c
+++ b/library/error.c
@@ -861,7 +861,7 @@
     if( use_ret == -(MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED) )
         mbedtls_snprintf( buf, buflen, "SHA256 - SHA-256 hardware accelerator failed" );
     if( use_ret == -(MBEDTLS_ERR_SHA256_BAD_INPUT_DATA) )
-        mbedtls_snprintf( buf, buflen, "SHA256 - Invalid input data" );
+        mbedtls_snprintf( buf, buflen, "SHA256 - SHA-256 input data was malformed" );
 #endif /* MBEDTLS_SHA256_C */
 
 #if defined(MBEDTLS_SHA512_C)