diff --git a/tests/suites/host_test.function b/tests/suites/host_test.function
index 475a9c835b..a99a7c7c83 100644
--- a/tests/suites/host_test.function
+++ b/tests/suites/host_test.function
@@ -180,24 +180,24 @@ static int parse_arguments(char *buf, size_t len, char **params,
         p++;
     }
 
-    /* Replace newlines, question marks and colons in strings */
+    /* Replace backslash escapes in strings */
     for (i = 0; i < cnt; i++) {
         p = params[i];
         q = params[i];
 
         while (*p != '\0') {
-            if (*p == '\\' && *(p + 1) == 'n') {
-                p += 2;
-                *(q++) = '\n';
-            } else if (*p == '\\' && *(p + 1) == ':') {
-                p += 2;
-                *(q++) = ':';
-            } else if (*p == '\\' && *(p + 1) == '?') {
-                p += 2;
-                *(q++) = '?';
-            } else {
-                *(q++) = *(p++);
+            if (*p == '\\') {
+                ++p;
+                switch (*p) {
+                    case 'n':
+                        *p = '\n';
+                        break;
+                    default:
+                        // Fall through to copying *p
+                        break;
+                }
             }
+            *(q++) = *(p++);
         }
         *q = '\0';
     }
diff --git a/tests/suites/test_suite_x509parse.data b/tests/suites/test_suite_x509parse.data
index a6b001fb15..db2fe56a5f 100644
--- a/tests/suites/test_suite_x509parse.data
+++ b/tests/suites/test_suite_x509parse.data
@@ -336,7 +336,7 @@ mbedtls_x509_csr_info:"data_files/server1.req.sha512":"CSR version   \: 1\nsubje
 
 X509 CSR Information RSA with SHA-256, containing commas
 depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_MD_CAN_SHA256:MBEDTLS_RSA_C:MBEDTS_X509_INFO
-mbedtls_x509_csr_info:"data_files/server1.req.commas.sha256":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL\, Commas, CN=PolarSSL Server 1\nsigned using  \: RSA with SHA-256\nRSA key size  \: 2048 bits\n"
+mbedtls_x509_csr_info:"data_files/server1.req.commas.sha256":"CSR version   \: 1\nsubject name  \: C=NL, O=PolarSSL\\, Commas, CN=PolarSSL Server 1\nsigned using  \: RSA with SHA-256\nRSA key size  \: 2048 bits\n"
 
 X509 CSR Information EC with SHA1
 depends_on:MBEDTLS_PK_CAN_ECDSA_SOME:MBEDTLS_PEM_PARSE_C:MBEDTLS_ECP_DP_SECP256R1_ENABLED:MBEDTLS_MD_CAN_SHA1:!MBEDTLS_X509_REMOVE_INFO
@@ -437,7 +437,7 @@ mbedtls_x509_dn_gets:"data_files/server2.crt":"issuer":"C=NL, O=PolarSSL, CN=Pol
 
 X509 Get Distinguished Name #5
 depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_RSA_C:MBEDTLS_MD_CAN_SHA1
-mbedtls_x509_dn_gets:"data_files/server1.commas.crt":"subject":"C=NL, O=PolarSSL\, Commas, CN=PolarSSL Server 1"
+mbedtls_x509_dn_gets:"data_files/server1.commas.crt":"subject":"C=NL, O=PolarSSL\\, Commas, CN=PolarSSL Server 1"
 
 X509 Get Modified DN #1
 depends_on:MBEDTLS_PEM_PARSE_C:MBEDTLS_RSA_C:MBEDTLS_MD_CAN_SHA1
@@ -3145,7 +3145,7 @@ x509_get_time:MBEDTLS_ASN1_UTC_TIME:"0002291212+0300":MBEDTLS_ERR_X509_INVALID_D
 
 X509 Get time (UTC invalid character in year)
 depends_on:MBEDTLS_X509_USE_C
-x509_get_time:MBEDTLS_ASN1_UTC_TIME:"0\1130231212Z":MBEDTLS_ERR_X509_INVALID_DATE:0:0:0:0:0:0
+x509_get_time:MBEDTLS_ASN1_UTC_TIME:"0\\1130231212Z":MBEDTLS_ERR_X509_INVALID_DATE:0:0:0:0:0:0
 
 X509 Get time (UTC invalid character in month)
 depends_on:MBEDTLS_X509_USE_C
diff --git a/tests/suites/test_suite_x509write.data b/tests/suites/test_suite_x509write.data
index bb40029bb9..cd1b0a3bd7 100644
--- a/tests/suites/test_suite_x509write.data
+++ b/tests/suites/test_suite_x509write.data
@@ -163,7 +163,7 @@ depends_on:MBEDTLS_MD_CAN_SHA256:MBEDTLS_PK_CAN_ECDSA_SIGN:MBEDTLS_ECDSA_DETERMI
 x509_crt_check:"data_files/server5.key":"":"C=NL,O=PolarSSL,CN=PolarSSL Server 1":"data_files/test-ca2.key":"PolarSSLTest":"C=NL,O=PolarSSL,CN=Polarssl Test EC CA":"01":"20190210144406":"20290210144406":MBEDTLS_MD_SHA256:0:0:"NULL":0:0:1:-1:"":2:0:"data_files/test-ca2.crt"
 
 X509 String to Names #1
-mbedtls_x509_string_to_names:"C=NL,O=Offspark\, Inc., OU=PolarSSL":"C=NL, O=Offspark\, Inc., OU=PolarSSL":0
+mbedtls_x509_string_to_names:"C=NL,O=Offspark\\, Inc., OU=PolarSSL":"C=NL, O=Offspark\\, Inc., OU=PolarSSL":0
 
 X509 String to Names #2
 mbedtls_x509_string_to_names:"C=NL, O=Offspark, Inc., OU=PolarSSL":"":MBEDTLS_ERR_X509_UNKNOWN_OID
@@ -175,10 +175,10 @@ X509 String to Names #4 (Name larger than 255 bytes)
 mbedtls_x509_string_to_names:"C=NL, O=1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456, OU=PolarSSL":"":MBEDTLS_ERR_X509_INVALID_NAME
 
 X509 String to Names #5 (Escape non-allowed characters)
-mbedtls_x509_string_to_names:"C=NL, O=Offspark\a Inc., OU=PolarSSL":"":MBEDTLS_ERR_X509_INVALID_NAME
+mbedtls_x509_string_to_names:"C=NL, O=Offspark\\a Inc., OU=PolarSSL":"":MBEDTLS_ERR_X509_INVALID_NAME
 
 X509 String to Names #6 (Escape at end)
-mbedtls_x509_string_to_names:"C=NL, O=Offspark\":"":MBEDTLS_ERR_X509_INVALID_NAME
+mbedtls_x509_string_to_names:"C=NL, O=Offspark\\":"":MBEDTLS_ERR_X509_INVALID_NAME
 
 Check max serial length
 x509_set_serial_check: