diff --git a/README.md b/README.md
index 8fc8d3d..794c3ee 100644
--- a/README.md
+++ b/README.md
@@ -56,6 +56,8 @@ Enumeration:
 Writing:
   --rbcd source         Operation to write or remove RBCD. Also used to pass in the source computer account used
                         for the attack.
+  --altsecid value      Operation to write the altSecurityIdentities attribute value, writes by default unless "
+                        --remove" is specified
   --spn value           Operation to write the servicePrincipalName attribute value, writes by default unless "
                         --remove" is specified
   --asrep               Operation to write the DONT_REQ_PREAUTH (0x400000) userAccountControl flag on a target
diff --git a/src/adws.py b/src/adws.py
index 2b5fe82..8964c02 100644
--- a/src/adws.py
+++ b/src/adws.py
@@ -1,6 +1,7 @@
 import datetime
 import logging
 import socket
+import re
 from base64 import b64decode
 from enum import IntFlag
 from typing import Self, Type
@@ -426,6 +427,13 @@ def _handle_str_to_xml(self, xmlstr: str) -> ElementTree.Element | None:
             soap message return by the server
         """
 
+        # handling of unescaped XML special characters in
+        # responses to ensure smooth parsing
+        m = re.search(r'<ad:value[^>]*>(X509:<[^>]+>(.*?))</ad:value>', xmlstr)
+        if m:
+            unescaped = m.groups()[0]
+            xmlstr = xmlstr.replace(unescaped, '<![CDATA[%s]]>' % unescaped)
+
         if ":Fault>" and ":Reason>" not in xmlstr:
             return ElementTree.fromstring(xmlstr)
 
diff --git a/src/soa.py b/src/soa.py
index e091db8..2414a6b 100644
--- a/src/soa.py
+++ b/src/soa.py
@@ -85,8 +85,9 @@ def getAccountDN(
     return dn
 
 
-def set_spn(
+def set_array_attribute(
     target: str,
+    attr: str,
     value: str,
     username: str,
     ip: str,
@@ -94,32 +95,34 @@ def set_spn(
     auth: NTLMAuth,
     remove: bool = False,
 ):
-    """Set a value in servicePrincipalName. Appends value to the 
-    attribute rather than replacing.
+    """Set a value in AD attribute that has isSingleValued=False
+        (e.g. servicePrincipalName, altSecurityIdentities).
+        Appends value to the attribute rather than replacing.
 
     Args:
         target (str): target samAccountName
-        value (str): value to append to the targets servicePrincipalName
+        attr (str): name of attribute to modify
+        value (str): value to append to the target's attribute
         username (str): user to authenticate as
         ip (str): the ip of the domain controller
         auth (NTLMAuth): authentication method
         remove (bool): Whether to remove the value
     """
 
-    dn = getAccountDN(target=target,username=username,ip=ip,domain=domain,auth=auth)
+    dn = getAccountDN(target=target, username=username, ip=ip, domain=domain, auth=auth)
     
     put_client = ADWSConnect.put_client(ip, domain, username, auth)
     
     put_client.put(
         object_ref=dn,
         operation="add" if not remove else "delete",
-        attribute="addata:servicePrincipalName",
+        attribute=f"addata:{attr}",
         data_type="string",
         value=value,
     )
         
     print(
-        f"[+] servicePrincipalName {value} {'removed' if remove else 'written'} successfully on {target}!"
+        f"[+] {attr} {value} {'removed' if remove else 'written'} successfully on {target}!"
     )
 
 def set_asrep(
@@ -412,6 +415,12 @@ def run_cli():
         metavar="source",
         help="Operation to write or remove RBCD. Also used to pass in the source computer account used for the attack.",
     )
+    writing.add_argument(
+        "--altsecid",
+        action="store",
+        metavar="value",
+        help='Operation to write the altSecurityIdentities attribute value, writes by default unless "--remove" is specified',
+    )
     writing.add_argument(
         "--spn",
         action="store",
@@ -503,6 +512,23 @@ def run_cli():
             auth=auth,
             remove=options.remove,
         )
+    elif options.altsecid != None:
+        if not options.account:
+            logging.critical(
+                'Please specify an account with "--account"'
+            )
+            raise SystemExit()
+        
+        set_array_attribute(
+            ip=remoteName,
+            domain=domain,
+            target=options.account,
+            attr='altSecurityIdentities',
+            value=options.altsecid,
+            username=username,
+            auth=auth,
+            remove=options.remove
+        )
     elif options.spn != None:
         if not options.account:
             logging.critical(
@@ -510,10 +536,11 @@ def run_cli():
             )
             raise SystemExit()
         
-        set_spn(
+        set_array_attribute(
             ip=remoteName,
             domain=domain,
             target=options.account,
+            attr='servicePrincipalName',
             value=options.spn,
             username=username,
             auth=auth,
diff --git a/src/soap_templates.py b/src/soap_templates.py
index eda1b0d..52a9681 100644
--- a/src/soap_templates.py
+++ b/src/soap_templates.py
@@ -100,9 +100,9 @@
                 <da:Change Operation="{operation}">
                     <da:AttributeType>{attribute}</da:AttributeType>
                     <da:AttributeValue>
-                        <ad:value xsi:type="xsd:{data_type}">{value}</ad:value>
+                        <ad:value xsi:type="xsd:{data_type}"><![CDATA[{value}]]></ad:value>
                     </da:AttributeValue>
                 </da:Change>
             </da:ModifyRequest>
         </s:Body>
-    </s:Envelope>"""
\ No newline at end of file
+    </s:Envelope>"""