101arrowz: >> Fflate >> 0.4.3 Security Vulnerabilities
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.
CVSS Score
6.6
EPSS Score
0.003
Published
2026-07-22