Fixes #6082: Support colons in webhook header values

Author: jeremystretch

docs/release-notes/version-2.10.md

@@ -16,6 +16,7 @@
 * [#6070](https://github.com/netbox-community/netbox/issues/6070) - Add missing `count_ipaddresses` attribute to VMInterface serializer
 * [#6073](https://github.com/netbox-community/netbox/issues/6073) - Permit users to manage their own REST API tokens without needing explicit permission
 * [#6081](https://github.com/netbox-community/netbox/issues/6081) - Fix interface connections REST API endpoint
+* [#6082](https://github.com/netbox-community/netbox/issues/6082) - Support colons in webhook header values
 * [#6108](https://github.com/netbox-community/netbox/issues/6108) - Do not infer tenant assignment from parent objects for prefixes, IP addresses
 * [#6117](https://github.com/netbox-community/netbox/issues/6117) - Handle exception when attempting to assign an MPTT-enabled model as its own parent
 * [#6131](https://github.com/netbox-community/netbox/issues/6131) - Correct handling of boolean fields when cloning objects

netbox/extras/models/models.py

@@ -140,7 +140,7 @@ def render_headers(self, context):
         ret = {}
         data = render_jinja2(self.additional_headers, context)
         for line in data.splitlines():
-            header, value = line.split(':')
+            header, value = line.split(':', 1)
             ret[header.strip()] = value.strip()
         return ret