While I'm not sure what exactly you considered to be the error, it seems to me there are multiple problems around here:

source openrc demo demo ; export TOKEN="$( openstack token issue -f value -c id )"

curl -s -H "Content-Type: application/json" -H "X-Auth-Token: $TOKEN" -X GET http://127.0.0.1:9696/v2.0/security-groups
works as expected

curl -s -H "Content-Type: application/json" -H "X-Auth-Token: $TOKEN" -X GET http://127.0.0.1:9696/v2.0/security-groups?tenant_id=$( openstack project show demo -f value -c id )
works as expected

curl -s -H "Content-Type: application/json" -H "X-Auth-Token: $TOKEN" -X GET http://127.0.0.1:9696/v2.0/security-groups?tenant_id=foobar
no response, client hangs

curl -s -H "Content-Type: application/json" -H "X-Auth-Token: $TOKEN" -X GET http://127.0.0.1:9696/v2.0/security-groups?tenant_id=$( uuid | tr -d - )
internal server error

source openrc admin admin ; export TOKEN="$( openstack token issue -f value -c id )"

curl -s -H "Content-Type: application/json" -H "X-Auth-Token: $TOKEN" -X GET http://127.0.0.1:9696/v2.0/security-groups
works as expected

curl -s -H "Content-Type: application/json" -H "X-Auth-Token: $TOKEN" -X GET http://127.0.0.1:9696/v2.0/security-groups?tenant_id=$( openstack project show admin -f value -c id )
works as expected

curl -s -H "Content-Type: application/json" -H "X-Auth-Token: $TOKEN" -X GET http://127.0.0.1:9696/v2.0/security-groups?tenant_id=foobar
echoes foobar in the response

curl -s -H "Content-Type: application/json" -H "X-Auth-Token: $TOKEN" -X GET http://127.0.0.1:9696/v2.0/security-groups?tenant_id=$( uuid | tr -d - )
echoes the random uuid in the response

I would say the 1) no response, 2) internal server error and 3) unvalidated echo cases are all bugs.

neutron server log for the no response case:

jan 22 15:13:06 devstack0 neutron-server[342671]: DEBUG neutron_lib.db.api [None req-f63b9ee0-bb5c-4e19-9150-3e0dd18a01b7 demo demo] Retry wrapper got retriable exception: Failed to create a duplicate DefaultSecurityGroup: for attribute(s) ['default_security_group.PRIMARY'] with value(s) foobar {{(pid=342671) wrapped /opt/stack/neutron-lib/neutron_lib/db/api.py:183}}

neutron server log for the internal server error:

jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource [None req-160228f5-d91d-4fc3-81a1-729056507e49 demo demo] index failed: No details.: TypeError: 'NoneType' object is not subscriptable
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource Traceback (most recent call last):
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron/neutron/api/v2/resource.py", line 98, in resource
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     result = method(request=request, **args)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron-lib/neutron_lib/db/api.py", line 139, in wrapped
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     setattr(e, '_RETRY_EXCEEDED', True)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_utils/excutils.py", line 220, in __exit__
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     self.force_reraise()
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_utils/excutils.py", line 196, in force_reraise
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     six.reraise(self.type_, self.value, self.tb)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/six.py", line 703, in reraise
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     raise value
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron-lib/neutron_lib/db/api.py", line 135, in wrapped
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     return f(*args, **kwargs)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_db/api.py", line 154, in wrapper
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     ectxt.value = e.inner_exc
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_utils/excutils.py", line 220, in __exit__
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     self.force_reraise()
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_utils/excutils.py", line 196, in force_reraise
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     six.reraise(self.type_, self.value, self.tb)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/six.py", line 703, in reraise
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     raise value
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_db/api.py", line 142, in wrapper
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     return f(*args, **kwargs)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron-lib/neutron_lib/db/api.py", line 183, in wrapped
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     LOG.debug("Retry wrapper got retriable exception: %s", e)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_utils/excutils.py", line 220, in __exit__
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     self.force_reraise()
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_utils/excutils.py", line 196, in force_reraise
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     six.reraise(self.type_, self.value, self.tb)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/six.py", line 703, in reraise
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     raise value
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron-lib/neutron_lib/db/api.py", line 179, in wrapped
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     return f(*dup_args, **dup_kwargs)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron/neutron/api/v2/base.py", line 369, in index
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     return self._items(request, True, parent_id)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron/neutron/api/v2/base.py", line 304, in _items
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     obj_list = obj_getter(request.context, **kwargs)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron-lib/neutron_lib/db/api.py", line 217, in wrapped
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     return method(*args, **kwargs)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron-lib/neutron_lib/db/api.py", line 139, in wrapped
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     setattr(e, '_RETRY_EXCEEDED', True)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_utils/excutils.py", line 220, in __exit__
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     self.force_reraise()
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_utils/excutils.py", line 196, in force_reraise
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     six.reraise(self.type_, self.value, self.tb)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/six.py", line 703, in reraise
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     raise value
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron-lib/neutron_lib/db/api.py", line 135, in wrapped
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     return f(*args, **kwargs)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_db/api.py", line 154, in wrapper
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     ectxt.value = e.inner_exc
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_utils/excutils.py", line 220, in __exit__
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     self.force_reraise()
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_utils/excutils.py", line 196, in force_reraise
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     six.reraise(self.type_, self.value, self.tb)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/six.py", line 703, in reraise
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     raise value
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_db/api.py", line 142, in wrapper
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     return f(*args, **kwargs)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron-lib/neutron_lib/db/api.py", line 183, in wrapped
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     LOG.debug("Retry wrapper got retriable exception: %s", e)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_utils/excutils.py", line 220, in __exit__
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     self.force_reraise()
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_utils/excutils.py", line 196, in force_reraise
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     six.reraise(self.type_, self.value, self.tb)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/six.py", line 703, in reraise
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     raise value
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron-lib/neutron_lib/db/api.py", line 179, in wrapped
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     return f(*dup_args, **dup_kwargs)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron/neutron/db/securitygroups_db.py", line 176, in get_security_groups
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     self._ensure_default_security_group(context, tenant_id)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron/neutron/db/securitygroups_db.py", line 918, in _ensure_default_security_group
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     return self.create_security_group(context, security_group,
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron-lib/neutron_lib/db/api.py", line 217, in wrapped
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     return method(*args, **kwargs)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron-lib/neutron_lib/db/api.py", line 139, in wrapped
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     setattr(e, '_RETRY_EXCEEDED', True)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_utils/excutils.py", line 220, in __exit__
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     self.force_reraise()
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_utils/excutils.py", line 196, in force_reraise
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     six.reraise(self.type_, self.value, self.tb)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/six.py", line 703, in reraise
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     raise value
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron-lib/neutron_lib/db/api.py", line 135, in wrapped
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     return f(*args, **kwargs)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_db/api.py", line 154, in wrapper
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     ectxt.value = e.inner_exc
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_utils/excutils.py", line 220, in __exit__
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     self.force_reraise()
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_utils/excutils.py", line 196, in force_reraise
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     six.reraise(self.type_, self.value, self.tb)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/six.py", line 703, in reraise
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     raise value
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_db/api.py", line 142, in wrapper
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     return f(*args, **kwargs)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron-lib/neutron_lib/db/api.py", line 183, in wrapped
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     LOG.debug("Retry wrapper got retriable exception: %s", e)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_utils/excutils.py", line 220, in __exit__
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     self.force_reraise()
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/oslo_utils/excutils.py", line 196, in force_reraise
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     six.reraise(self.type_, self.value, self.tb)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/usr/local/lib/python3.8/dist-packages/six.py", line 703, in reraise
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     raise value
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron-lib/neutron_lib/db/api.py", line 179, in wrapped
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     return f(*dup_args, **dup_kwargs)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron/neutron/db/securitygroups_db.py", line 149, in create_security_group
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     secgroup_dict = self._make_security_group_dict(sg)
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource   File "/opt/stack/neutron/neutron/db/securitygroups_db.py", line 327, in _make_security_group_dict
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource     res = {'id': security_group['id'],
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource TypeError: 'NoneType' object is not subscriptable
jan 22 15:15:25 devstack0 neutron-server[342672]: ERROR neutron.api.v2.resource