Vulnerability library
Security checkSeptember 02, 2026

fast-uri vulnerable to host confusion via skipped IDN canonicalization on scheme-relative references

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High severitynpmfast-uri

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Description

fast-uri canonicalizes a host to its ASCII form only when the input carries an explicit scheme.

Recommendation

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

  • Affected version(s): **>= 4.0.1, < 4.1.3 >= 3.1.3, < 3.1.6 >= 2.4.2, < 2.4.5**
  • Patched version(s): **4.1.3 3.1.6 2.4.5**

References

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See something that needs correcting? Let us knowUpdated September 02, 2026