Vulnerability library
Security checkOctober 05, 2026

fast-copy: Stack exhaustion in fast-copy when copying deeply-nested values

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Medium severitynpmfast-copy

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Description

fast-copy traverses values recursively with no bound on depth. Copying a sufficiently deeply-nested value exhausts the JavaScript call stack and throws a native RangeError: Maximum call stack size exceeded from inside the library.

Recommendation

Update the fast-copy package to the latest compatible version. Followings are version details:

  • Affected version(s): **< 2.2.0 >= 3.0.0, < 3.1.0 >= 4.0.0, < 4.1.0**
  • Patched version(s): **2.2.0 3.1.0 4.1.0**

References

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Related Issues

See something that needs correcting? Let us knowUpdated October 05, 2026