oledump.plugin_biff error

[CalLight]

Affected tool:
olevba

Running olevba on an xls with Excel 4 macro results in the following error:
malware hash - 4c6ec69af9dfb446273a38be73be83a613018b1b6a64ab1386cc798637a63832

https://www.hybrid-analysis.com/sample/4c6ec69af9dfb446273a38be73be83a613018b1b6a64ab1386cc798637a63832?environmentId=100

olevba 0.54.1 on Python 2.7.16 - http://decalage.info/python/oletools
===============================================================================
FILE: 4c6ec69af9dfb446273a38be73be83a613018b1b6a64ab1386cc798637a63832.xls
Type: OLE
ERROR    Error when running oledump.plugin_biff, please report to https://github.com/decalage2/oletools/issues
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/oletools/olevba.py", line 3106, in detect_xlm_macros
    self.xlm_macros = biff_plugin.Analyze()
  File "/usr/local/lib/python2.7/dist-packages/oletools/thirdparty/oledump/plugin_biff.py", line 1008, in Analyze
    strings += ' '.join(values[0])
TypeError: sequence item 0: expected string, bytearray found
No VBA macros found.

Version information:

• OS: Linux
• OS version: Kali 64 bit
• Python version: 2.7.16
• oletools version: 0.54

[enzok]

The STRING record is receiving a list of bytearray values and then it's trying to do a string join on them, hence the error.

[decalage2]

This issue is now fixed both for Python 2 and 3.