GHSA-px8p-9vwx-vf98MediumCVSS 7.5
fflate unzipSync can enter an infinite loop when parsing malformed ZIP64 archives
🔗 CVE IDs covered (1)
📋 Description
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.
🎯 Affected products5
- npm/fflate:>= 0.4.5, < 0.4.9
- npm/fflate:>= 0.5.0, < 0.5.4
- npm/fflate:>= 0.6.0, < 0.6.11
- npm/fflate:>= 0.7.0, < 0.7.5
- npm/fflate:>= 0.8.0, < 0.8.3
🔗 References (5)
- 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