capa very verbose ghidra backend breaks

[kingspear-dd]

Description

capa -vv -b ghidra <mysample> broke and gave an error (I reproduced the error several times, including in debug mode -> output attached as capabvv.txt) where capa -b ghidra <mysample> gave good output (capab.txt). This was sample specific, a few other samples I tested did not produce this error.

<mysample> SHA256: 00ae07c9fe63b080181b8a6d59c6b3b6f9913938858829e5a42ab90fb72edf7a (from: https://github.com/MalwareSamples/Linux-Malware-Samples)

I was running this on REMnux using the latest version of capa.

Steps to Reproduce

Execute capa -vv -b ghidra <mysample>

Expected behavior:

capa runs the ghidra backend and does -vv output.

Actual behavior:

breaks on a TypeError: expected string or bytes-like object (end of debug file)

capab.txt
capabvv.txt

Versions

capa 9.4.0
ghidra 12.1.2
python 3.12.3

Additional Information

[williballenthin]

DEBUG    capa.capabilities.common: analyzed file and extracted 50433 features                                           common.py:53
Traceback (most recent call last):
  File "main.py", line 1164, in <module>
  File "main.py", line 1057, in main
  File "capa/render/vverbose.py", line 540, in render
  File "capa/render/vverbose.py", line 533, in render_vverbose
  File "capa/render/vverbose.py", line 516, in render_rules
  File "capa/render/vverbose.py", line 332, in render_match
  File "capa/render/vverbose.py", line 329, in render_match
  File "capa/render/vverbose.py", line 280, in render_node
  File "capa/render/vverbose.py", line 162, in render_statement
  File "capa/render/utils.py", line 33, in bold2
  File "rich/markup.py", line 66, in escape
TypeError: expected string or bytes-like object
[PYI-3655:ERROR] Failed to execute script 'main' due to unhandled exception!

[abhinav-phi]

Hi @williballenthin,

I'd like to work on this issue. I'll investigate the root cause of the TypeError in the very verbose renderer, reproduce it locally, and submit a fix with appropriate tests if I can identify the underlying issue.