---
id: CVE-2026-122146
title: 101arrowz fflate index.mjs unzipSync memory corruption
summary: >-
  A weakness has been identified in 101arrowz fflate up to 0.8.3. This issue
  affects the function unzipSync of the file esm/index.mjs. This manipulation
  causes memory corruption. It is possible to initiate the attack remotely. The
  exploit …
severity: high
cvss: 7.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:C'
cvssSource: cna
cwe:
  - CWE-119
vendor: 101arrowz
product: fflate
affected:
  - fflate 0.8.0
  - fflate 0.8.1
  - fflate 0.8.2
  - fflate 0.8.3
ssvc:
  exploitation: poc
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-11-05T20:31:57.574774Z'
exploitAvailable: true
published: '2026-11-05'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T20:32:08.969Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-122146'
references:
  - url: 'https://vuldb.com/vuln/431150'
    label: VDB-431150 | 101arrowz fflate index.mjs unzipSync memory corruption
  - url: 'https://vuldb.com/vuln/431150/cti'
    label: 'VDB-431150 | CTI Indicators (IOB, IOC, IOA)'
  - url: 'https://vuldb.com/cve/CVE-2026-122146'
    label: CVE-2026-122146 | CVE Analysis and Report
  - url: 'https://vuldb.com/submit/1027352'
    label: 'Submit #1027352 | fflate <=0.8.3 Memory Corruption'
  - url: 'https://github.com/ictrun/java/issues/9'
tags:
  - cve.org
  - exploit-available
epss: 0.00293
epssPercentile: 0.22096
ingestedAt: '2026-11-05T22:38:31.835Z'
---

## Overview

A weakness has been identified in 101arrowz fflate up to 0.8.3. This issue affects the function unzipSync of the file esm/index.mjs. This manipulation causes memory corruption. It is possible to initiate the attack remotely. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.

## Affected

- `fflate 0.8.0`
- `fflate 0.8.1`
- `fflate 0.8.2`
- `fflate 0.8.3`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.