fix(compliance): handle ZeroDivision error from Prowler ThreatScore

[pedrooot]

Description

This pull request improves the robustness and clarity of the threat score calculation and display logic in the prowler_threatscore.py output module. The key changes ensure that division by zero is avoided and that the threat score output is accurate and visually consistent, even when all findings are muted or a pillar's maximum score is zero.

Improvements to threat score calculation and display:

• Added a check to handle cases where max_score_per_pillar[pillar] is zero, setting the pillar score to 100% and using a green color to indicate no risk; otherwise, the score is calculated as before and shown in red.
• Updated the calculation of the generic threat score to handle division by zero when max_generic_score is zero, defaulting the score to 100% in this case.

Steps to review

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Checklist

• Are there new checks included in this PR? Yes / No
  • If so, do we need to update permissions for the provider? Please review this carefully.
• Review if the code is being covered by tests.
• Review if code is being documented following this specification https://github.com/google/styleguide/blob/gh-pages/pyguide.md#38-comments-and-docstrings
• Review if backport is needed.
• Review if is needed to change the Readme.md
• Ensure new entries are added to CHANGELOG.md, if applicable.

UI

• All issue/task requirements work as expected on the UI
• Screenshots/Video of the functionality flow (if applicable) - Mobile (X < 640px)
• Screenshots/Video of the functionality flow (if applicable) - Table (640px > X < 1024px)
• Screenshots/Video of the functionality flow (if applicable) - Desktop (X > 1024px)
• Ensure new entries are added to CHANGELOG.md, if applicable.

API

• Verify if API specs need to be regenerated.
• Check if version updates are required (e.g., specs, Poetry, etc.).
• Ensure new entries are added to CHANGELOG.md, if applicable.

License

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[github-actions]

✅ All necessary CHANGELOG.md files have been updated.

[github-actions]

✅ Conflict Markers Resolved

All conflict markers have been successfully resolved in this pull request.

[codecov]

Codecov Report

❌ Patch coverage is 0% with 9 lines in your changes missing coverage. Please review.
✅ Project coverage is 69.53%. Comparing base (43875b6) to head (be88488).
⚠️ Report is 7 commits behind head on master.

❗ There is a different number of reports uploaded between BASE (43875b6) and HEAD (be88488). Click for more details.

HEAD has 8 uploads less than BASE

Flag	BASE (43875b6)	HEAD (be88488)
prowler-py3.9-config	1	0
prowler-py3.11-config	1	0
prowler-py3.10-config	1	0
prowler-py3.12-config	1	0
prowler-py3.11-gcp	1	0
prowler-py3.9-gcp	1	0
prowler-py3.10-gcp	1	0
prowler-py3.12-gcp	1	0

Additional details and impacted files

@@             Coverage Diff             @@
##           master    #9653       +/-   ##
===========================================
- Coverage   92.27%   69.53%   -22.74%     
===========================================
  Files         128       84       -44     
  Lines        3210     5896     +2686     
===========================================
+ Hits         2962     4100     +1138     
- Misses        248     1796     +1548     

Flag	Coverage Δ
prowler-py3.10-config	?
prowler-py3.10-gcp	?
prowler-py3.10-lib	69.53% <0.00%> (?)
prowler-py3.11-config	?
prowler-py3.11-gcp	?
prowler-py3.11-lib	69.53% <0.00%> (?)
prowler-py3.12-config	?
prowler-py3.12-gcp	?
prowler-py3.12-lib	69.53% <0.00%> (?)
prowler-py3.9-config	?
prowler-py3.9-gcp	?
prowler-py3.9-lib	69.53% <0.00%> (?)

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
prowler	69.53% <0.00%> (-22.74%)	⬇️
api	∅ <ø> (∅)

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[github-actions]

🔒 Container Security Scan

Image: prowler:eab425b
Last scan: 2025-12-23 08:26:10 UTC

📊 Vulnerability Summary

Severity	Count
🔴 Critical	3
Total	3

3 package(s) affected

⚠️ Action Required

Critical severity vulnerabilities detected. These should be addressed before merging:

• Review the detailed scan results
• Update affected packages to patched versions
• Consider using a different base image if updates are unavailable

---

📋 Resources:

• Download full report (see artifacts)
• View in Security tab
• Scanned with Trivy

[prowler-bot]

💚 All backports created successfully

Status	Branch	Result
✅	v5.16

Questions ?

Please refer to the Backport tool documentation and see the Github Action logs for details