Threat Modeling Tool corrupting .tb7 files, how to obtain prior version

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Summary

A critical bug in the latest Microsoft Threat Modeling Tool version causes corruption in .tb7 template files when adding new stencil attributes. This results in attribute lists being randomly duplicated across all stencils, rendering files unusable.

Root Cause

  • Binding defects in XML serialization logic:
    The tool incorrectly associates new attribute additions with existing stencils due to flawed XML ID mapping.
  • Missing validation:
    No schema or integrity checks occur post-modification to ensure stencil isolation.
  • Windows 11 compatibility gap:
    Path handling discrepancies between Windows 10 and Windows 11 exacerbate serialization defects.

Why This Happens in Real Systems

  • Serialization frameworks often fail to enforce object-state isolation when modifying nested entities in XML/JSON structures.
  • Untested upgrade paths emerge from OS-specific file I/O behaviors overlooked in QA pipelines.
  • Absence of idempotent operations makes “add” actions hazardous when shared references exist.

Real-World Impact

  • Template unusability: Engineers cannot create or modify threat models.
  • Workflow paralysis: Teams cannot progress security-critical projects.
  • Data loss: Manual reconstruction of corrupted .tb7 files incurs hours of wasted effort.

Example or Code

(Illustrative XML snippet showing corruption) 



  




   
  <Attribute