diff --git a/tests/suites/test_suite_x509parse.data b/tests/suites/test_suite_x509parse.data
index 5e73613..2829cca 100644
--- a/tests/suites/test_suite_x509parse.data
+++ b/tests/suites/test_suite_x509parse.data
@@ -1036,7 +1036,7 @@
 x509parse_crt:"30153000300d06092a864886f70d01010b0500030200ff":"":MBEDTLS_ERR_X509_INVALID_FORMAT + MBEDTLS_ERR_ASN1_OUT_OF_DATA
 
 X509 Certificate ASN1 (TBSCertificate, no version tag, serial missing)
-x509parse_crt:"3003300100":"":MBEDTLS_ERR_X509_INVALID_SERIAL + MBEDTLS_ERR_ASN1_UNEXPECTED_TAG
+x509parse_crt:"3016300100300d06092a864886f70d01010b0500030200ff":"":MBEDTLS_ERR_X509_INVALID_SERIAL + MBEDTLS_ERR_ASN1_UNEXPECTED_TAG
 
 X509 Certificate ASN1 (TBSCertificate, valid outer version tag, no outer length)
 x509parse_crt:"30163001a0300d06092a864886f70d01010b0500030200ff":"":MBEDTLS_ERR_X509_INVALID_FORMAT + MBEDTLS_ERR_ASN1_OUT_OF_DATA
@@ -1071,12 +1071,18 @@
 X509 Certificate ASN1 (TBSCertificate, serial missing)
 x509parse_crt:"301a3005a003020102300d06092a864886f70d01010b0500030200ff":"":MBEDTLS_ERR_X509_INVALID_SERIAL + MBEDTLS_ERR_ASN1_OUT_OF_DATA
 
-X509 Certificate ASN1 (TBSCertificate, incorrect serial tag)
+X509 Certificate ASN1 (TBSCertificate, invalid serial, tag wrong)
 x509parse_crt:"301b3006a00302010200300d06092a864886f70d01010b0500030200ff":"":MBEDTLS_ERR_X509_INVALID_SERIAL + MBEDTLS_ERR_ASN1_UNEXPECTED_TAG
 
-X509 Certificate ASN1 (TBSCertificate, incorrect serial length)
+X509 Certificate ASN1 (TBSCertificate, invalid serial, length missing)
 x509parse_crt:"301b3006a00302010282300d06092a864886f70d01010b0500030200ff":"":MBEDTLS_ERR_X509_INVALID_SERIAL + MBEDTLS_ERR_ASN1_OUT_OF_DATA
 
+X509 Certificate ASN1 (TBSCertificate, invalid serial, invalid length encoding)
+x509parse_crt:"301c3007a0030201028285300d06092a864886f70d01010b0500030200ff":"":MBEDTLS_ERR_X509_INVALID_SERIAL + MBEDTLS_ERR_ASN1_INVALID_LENGTH
+
+X509 Certificate ASN1 (TBSCertificate, invalid serial, length out of bounds)
+x509parse_crt:"301c3007a0030201028201300d06092a864886f70d01010b0500030200ff":"":MBEDTLS_ERR_X509_INVALID_SERIAL + MBEDTLS_ERR_ASN1_OUT_OF_DATA
+
 X509 Certificate ASN1 (TBSCertificate, correct serial, no alg)
 x509parse_crt:"3020300ba0030201028204deadbeef300d06092a864886f70d01010b0500030200ff":"":MBEDTLS_ERR_X509_INVALID_ALG + MBEDTLS_ERR_ASN1_OUT_OF_DATA