Vulnerability library
Security checkMarch 27, 2026

Handlebars.js has JavaScript Injection via AST Type Confusion by tampering @partial-block

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High severitynpmhandlebars

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Description

The @partial-block special variable is stored in the template data context and is reachable and mutable from within a template via helpers that accept arbitrary objects.

Recommendation

Update the handlebars package to the latest compatible version. Followings are version details:

  • Affected version(s): >= 4.0.0, <= 4.7.8
  • Patched version(s): 4.7.9

References

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See something that needs correcting? Let us knowUpdated March 27, 2026