diff --git a/decnet/templates/_shared/ntlmssp.py b/decnet/templates/_shared/ntlmssp.py
index b0271a9a..95db7c66 100644
--- a/decnet/templates/_shared/ntlmssp.py
+++ b/decnet/templates/_shared/ntlmssp.py
@@ -120,7 +120,7 @@ def parse_type3(blob: bytes) -> Optional[dict]:
     if domain:
         principal = f"{domain}\\{username}"
     else:
-        principal = username or None
+        principal = username
 
     return {
         "username": username,
diff --git a/decnet/templates/conpot/syslog_bridge.py b/decnet/templates/conpot/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/conpot/syslog_bridge.py
+++ b/decnet/templates/conpot/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/docker_api/syslog_bridge.py b/decnet/templates/docker_api/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/docker_api/syslog_bridge.py
+++ b/decnet/templates/docker_api/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/elasticsearch/syslog_bridge.py b/decnet/templates/elasticsearch/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/elasticsearch/syslog_bridge.py
+++ b/decnet/templates/elasticsearch/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/ftp/syslog_bridge.py b/decnet/templates/ftp/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/ftp/syslog_bridge.py
+++ b/decnet/templates/ftp/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/http/syslog_bridge.py b/decnet/templates/http/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/http/syslog_bridge.py
+++ b/decnet/templates/http/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/https/syslog_bridge.py b/decnet/templates/https/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/https/syslog_bridge.py
+++ b/decnet/templates/https/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/imap/syslog_bridge.py b/decnet/templates/imap/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/imap/syslog_bridge.py
+++ b/decnet/templates/imap/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/k8s/syslog_bridge.py b/decnet/templates/k8s/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/k8s/syslog_bridge.py
+++ b/decnet/templates/k8s/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/ldap/syslog_bridge.py b/decnet/templates/ldap/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/ldap/syslog_bridge.py
+++ b/decnet/templates/ldap/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/llmnr/syslog_bridge.py b/decnet/templates/llmnr/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/llmnr/syslog_bridge.py
+++ b/decnet/templates/llmnr/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/mongodb/syslog_bridge.py b/decnet/templates/mongodb/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/mongodb/syslog_bridge.py
+++ b/decnet/templates/mongodb/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/mqtt/syslog_bridge.py b/decnet/templates/mqtt/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/mqtt/syslog_bridge.py
+++ b/decnet/templates/mqtt/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/mssql/syslog_bridge.py b/decnet/templates/mssql/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/mssql/syslog_bridge.py
+++ b/decnet/templates/mssql/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/mysql/syslog_bridge.py b/decnet/templates/mysql/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/mysql/syslog_bridge.py
+++ b/decnet/templates/mysql/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/pop3/syslog_bridge.py b/decnet/templates/pop3/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/pop3/syslog_bridge.py
+++ b/decnet/templates/pop3/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/postgres/syslog_bridge.py b/decnet/templates/postgres/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/postgres/syslog_bridge.py
+++ b/decnet/templates/postgres/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/rdp/ntlmssp.py b/decnet/templates/rdp/ntlmssp.py
index b0271a9a..95db7c66 100644
--- a/decnet/templates/rdp/ntlmssp.py
+++ b/decnet/templates/rdp/ntlmssp.py
@@ -120,7 +120,7 @@ def parse_type3(blob: bytes) -> Optional[dict]:
     if domain:
         principal = f"{domain}\\{username}"
     else:
-        principal = username or None
+        principal = username
 
     return {
         "username": username,
diff --git a/decnet/templates/rdp/syslog_bridge.py b/decnet/templates/rdp/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/rdp/syslog_bridge.py
+++ b/decnet/templates/rdp/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/redis/syslog_bridge.py b/decnet/templates/redis/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/redis/syslog_bridge.py
+++ b/decnet/templates/redis/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/sip/syslog_bridge.py b/decnet/templates/sip/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/sip/syslog_bridge.py
+++ b/decnet/templates/sip/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/smb/ntlmssp.py b/decnet/templates/smb/ntlmssp.py
index b0271a9a..95db7c66 100644
--- a/decnet/templates/smb/ntlmssp.py
+++ b/decnet/templates/smb/ntlmssp.py
@@ -120,7 +120,7 @@ def parse_type3(blob: bytes) -> Optional[dict]:
     if domain:
         principal = f"{domain}\\{username}"
     else:
-        principal = username or None
+        principal = username
 
     return {
         "username": username,
diff --git a/decnet/templates/smb/syslog_bridge.py b/decnet/templates/smb/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/smb/syslog_bridge.py
+++ b/decnet/templates/smb/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/smtp/syslog_bridge.py b/decnet/templates/smtp/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/smtp/syslog_bridge.py
+++ b/decnet/templates/smtp/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/snmp/syslog_bridge.py b/decnet/templates/snmp/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/snmp/syslog_bridge.py
+++ b/decnet/templates/snmp/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/ssh/syslog_bridge.py b/decnet/templates/ssh/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/ssh/syslog_bridge.py
+++ b/decnet/templates/ssh/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/syslog_bridge.py b/decnet/templates/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/syslog_bridge.py
+++ b/decnet/templates/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/telnet/syslog_bridge.py b/decnet/templates/telnet/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/telnet/syslog_bridge.py
+++ b/decnet/templates/telnet/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/tftp/syslog_bridge.py b/decnet/templates/tftp/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/tftp/syslog_bridge.py
+++ b/decnet/templates/tftp/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None
diff --git a/decnet/templates/vnc/syslog_bridge.py b/decnet/templates/vnc/syslog_bridge.py
index 7bd1e33f..44cf514a 100644
--- a/decnet/templates/vnc/syslog_bridge.py
+++ b/decnet/templates/vnc/syslog_bridge.py
@@ -13,6 +13,7 @@ Facility: local0 (16). SD element ID uses PEN 55555.
 """
 
 import base64
+import binascii
 import re
 from datetime import datetime, timezone
 from typing import Any, Optional
@@ -144,7 +145,7 @@ def classify_authorization(header_value: Optional[str]) -> Optional[dict[str, An
     if scheme == "basic":
         try:
             decoded = base64.b64decode(rest, validate=True).decode("utf-8", errors="replace")
-        except (ValueError, base64.binascii.Error):
+        except (ValueError, binascii.Error):
             return None
         if ":" not in decoded:
             return None