---
id: CVE-2026-82522
title: >-
  libjxl before 0.12 contains an integer underflow vulnerability in the
  container box parser that allows remote attackers to inject arbitrary metadata
  by exploiting 64-bit box size truncation to size_t on 32-bit platforms
summary: >-
  libjxl before 0.12 contains an integer underflow vulnerability in the
  container box parser that allows remote attackers to inject arbitrary metadata
  by exploiting 64-bit box size truncation to size_t on 32-bit platforms.
  Attackers can su…
severity: medium
cvss: 5.4
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N'
cwe:
  - CWE-681
published: '2026-09-02'
updated: '2026-09-23'
sourceUpdated: '2026-09-23T17:17:43.213'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-82522'
references:
  - url: >-
      https://github.com/libjxl/libjxl/commit/22ad80af1454f0444ea34115e49ed40517147d68
    label: disclosure@vulncheck.com
  - url: 'https://github.com/libjxl/libjxl/pull/4885'
    label: disclosure@vulncheck.com
  - url: 'https://github.com/libjxl/libjxl/releases/tag/v0.12.0'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/libjxl-container-box-parser-integer-underflow-via-32-bit-size-truncation
    label: disclosure@vulncheck.com
tags:
  - nvd
epss: 0.00407
epssPercentile: 0.3227
ingestedAt: '2026-09-23T17:28:14.821Z'
---

## Overview

libjxl before 0.12 contains an integer underflow vulnerability in the container box parser that allows remote attackers to inject arbitrary metadata by exploiting 64-bit box size truncation to size_t on 32-bit platforms. Attackers can supply a crafted JPEG XL file causing the decoder to parse attacker-controlled codestream bytes as phantom box headers, enabling injection of arbitrary metadata (Exif, XMP, IPTC, JUMBF) and potential out-of-bounds reads.

## Remediation

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