CVE-2026-45820

Summary

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 Software

VendorProductVersion RangeStatus
101arrowzfflate0.4.5 <= 0.4.8affected
101arrowzfflate0.5.0 <= 0.5.3affected
101arrowzfflate0.6.0 <= 0.6.10affected
101arrowzfflate0.7.0 <= 0.7.4affected
101arrowzfflate0.8.0 <= 0.8.2affected

Weaknesses

  • CWE-835: CWE-835 Loop with Unreachable Exit Condition ('Infinite Loop')
  • CWE-400: CWE-400 Uncontrolled Resource Consumption

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: yes
    • Technical Impact: partial

References