CVE-2026-45820

MEDIUM
MEDIUM Priority: 0.02 BB Relevance: 73/100
Published: 2026-07-22 Modified: 2026-10-24 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth No Interaction

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: None
S: N
AT: None
VC: None
VI: None
VA: High

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.

Weakness Classification (2)

Affected Software (1)

VendorProductVersion
101arrowz fflate < 0.8.2

Bug Bounty Relevance

73 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity
✓ No user interaction

CVSS Score

6.6 / 10.0 v4.0
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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:N/AU:Y/R:U/V:D/RE:M/U:Amber

EPSS — Exploitation Probability

0.28%
Raw Score 0.002790
Percentile 20.3%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00279
2026-10-28
0.00279

Intelligence Sources

nvd ref →