Fix splitlines bug.

[unsub42]

Description

There are a number of connectors (which specific ones is still under investigation; but at least Mandiant and Domaintools contribute to this issue) that provide description fields containing UTF-16 characters. Some of these UTF-16 characters include the 0x85 character. This is treated as a line terminator by the python splitlines function (it is an old IBM mainframe line terminator). When these characters are encountered by the SSEclient within the pycti library the JSON bundles are split at the 0x85 character causing the connector to generate an exception when processing json.loads.

Environment

1. OS (where OpenCTI server runs): Ubuntu 22.02
2. OpenCTI version: 5.7.6 and earlier
3. OpenCTI client: python
4. Other environment details: dockerized version

Reproducible Steps

Steps to create the smallest reproducible scenario:

1. Run backup-files stream connector
2. wait for the offending data to be processed through the stream
3. backup-files exception:
   Traceback (most recent call last):
   File "/usr/local/lib/python3.10/site-packages/pycti/connector/opencti_connector_helper.py", line 460, in run
   self.callback(msg)
   File "/opt/opencti-highside-sync/connectors-master/stream/backup-files/src/backup-files.py", line 78, in _process_message
   data = json.loads(msg.data)
   ujson.JSONDecodeError: Unmatched '"' when decoding 'string'
   Terminated

Expected Output

The bundle in question written to an output file.

Actual Output

The bundle does not get written, and the backup-files connector restarts at the last saved timestamp,
and re-processes files until it gets to the bundle in question, and then dies again. The process repeats
until the connector is stopped.

Additional information

N/A

Screenshots (optional)

N/A

[unsub42]

@richard-julien This is the issue I discussed in email.

[unsub42]

Bumping this up again. This problem has re-occurred (and my local workaround was not in place at the time). A Shodan enrichment for the IP address: 149.210.166.136 contains 0xc2 0x85 (UTF-16 character) in the description. This causes the SSEclient to split on these characters disrupting processing of stream data.