chore: bump up fflate version to v0.8.3 [SECURITY]

[renovate]

This PR contains the following updates:

Package	Change	Age	Confidence
fflate (source)	0.8.2 → 0.8.3

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

CVE-2026-45820 / GHSA-px8p-9vwx-vf98

More information

Details

fflate through 0.8.2 is vulnerable to denial of service via an infinite loop in unzipSync(). A crafted ZIP archive with a central directory entry declaring compressed_size=0xFFFFFFFF (ZIP64 sentinel) but missing the required ZIP64 extra field tag 0x0001 causes z64e() to loop indefinitely due to out-of-bounds reads returning undefined, which coerces to 0, keeping the loop condition permanently true.

Severity

• CVSS Score: 6.6 / 10 (Medium)
• Vector String: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/S:N/AU:Y/R:U/V:D/RE:M/U:Amber

References

• https://nvd.nist.gov/vuln/detail/CVE-2026-45820
• https://github.com/101arrowz/fflate/blob/f7873560ad229c22c4b23b06c6a3806ffde77569/src/index.ts#L2714
• https://github.com/101arrowz/fflate/commit/e6d5e6e1076892f72770ac732d83c81da9f3316e
• https://github.com/101arrowz/fflate/releases/tag/v0.8.3
• https://github.com/advisories/GHSA-px8p-9vwx-vf98

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

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Release Notes

101arrowz/fflate (fflate)

v0.8.3

Compare Source

• Fix buffer over-read for Zip64 extra fields
• Support sync flushes (Z_SYNC_FLUSH in zlib)
  • Allows for immediate decompression of all pushed bytes
  • Enables DEFLATE stream concatenation
• Fix zip/zipSync when using cross-realm Uint8Array
• Improve Zip64 support for streamed or undersized archives
• Update performance estimates in README
• Fix typings for TypeScript v5.7+
• Reduce memory consumption after compression stream completion

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