---
id: CVE-2026-112403
title: 'Pillow: Heap buffer overflow in ImagingJpegDecode'
summary: >-
  Pillow is a Python imaging library. Prior to 13.0.0, Pillow's JPEG decoder can
  write a full-width scanline into a buffer sized for a requested draft scale.
  ImagingJpegDecode does not verify libjpeg's actual output width and component
  cou…
severity: critical
cvss: 9.2
cvssVector: 'CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'
cvssSource: cna
cwe:
  - CWE-122
vendor: python-pillow
product: Pillow
affected:
  - Pillow < 13.0.0
published: '2026-10-19'
updated: '2026-10-19'
sourceUpdated: '2026-10-19T21:22:21.077Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-112403'
references:
  - url: >-
      https://github.com/python-pillow/Pillow/security/advisories/GHSA-8g5g-8vmr-9782
    label: >-
      https://github.com/python-pillow/Pillow/security/advisories/GHSA-8g5g-8vmr-9782
  - url: >-
      https://github.com/python-pillow/Pillow/commit/242a059aedc1935097d9aa1dc3f099750467ba75
    label: >-
      https://github.com/python-pillow/Pillow/commit/242a059aedc1935097d9aa1dc3f099750467ba75
  - url: 'https://github.com/python-pillow/Pillow/releases/tag/13.0.0'
    label: 'https://github.com/python-pillow/Pillow/releases/tag/13.0.0'
tags:
  - cve.org
ingestedAt: '2026-10-19T21:43:56.119Z'
---

## Overview

Pillow is a Python imaging library. Prior to 13.0.0, Pillow's JPEG decoder can write a full-width scanline into a buffer sized for a requested draft scale. ImagingJpegDecode does not verify libjpeg's actual output width and component count after scaling is requested, and an 8-bit lossless SOF3 JPEG decoded by a build linked to libjpeg-turbo 3.x can ignore the requested downscaling geometry. An attacker can supply such a JPEG to an application that uses draft() or thumbnail() to request downscaling. This can corrupt heap memory, crash the process, or potentially allow code execution. Older libjpeg-turbo 2.x and IJG builds reject the SOF3 input. This issue is fixed in version 13.0.0.

## Affected

- `Pillow < 13.0.0`

## Remediation

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