Vulnerability library
Security checkSeptember 03, 2026

fflate unzipSync can enter an infinite loop when parsing malformed ZIP64 archives

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Medium severitynpmfflate

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Description

fflate through 0.8.2 is vulnerable to denial of service via an infinite loop in unzipSync().

Recommendation

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

  • Affected version(s): **>= 0.8.0, < 0.8.3 >= 0.7.0, < 0.7.5 >= 0.6.0, < 0.6.11 >= 0.5.0, < 0.5.4 >= 0.4.5, < 0.4.9**
  • Patched version(s): **0.8.3 0.7.5 0.6.11 0.5.4 0.4.9**

References

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Related Issues

See something that needs correcting? Let us knowUpdated September 03, 2026