---
id: CVE-2026-91059
title: >-
  JPEG decoder: a duplicate SOF0 after SOS publishes a pixelmap that misreports
  its own allocation size
summary: >-
  The GUIX JPEG software decoder enforces no ordering on JPEG markers. A file
  that places a second `SOF0` frame header after `SOS` re-runs the frame header
  parser after the output buffer has already been allocated and its geometry
  latched.…
severity: medium
cvss: 6.8
cvssVector: 'CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:N/VA:L/SC:N/SI:N/SA:N'
cvssSource: cna
cwe:
  - CWE-125
vendor: Eclipse Foundation
product: GUIX
affected:
  - GUIX <= 6.5.1.202602a
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-10-20T15:23:51.302174Z'
published: '2026-10-20'
updated: '2026-10-20'
sourceUpdated: '2026-10-20T15:24:14.860Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-91059'
references:
  - url: >-
      https://github.com/eclipse-threadx/guix/security/advisories/GHSA-cxf2-pgvg-pcw3
tags:
  - cve.org
ingestedAt: '2026-10-20T15:09:24.111Z'
---

## Overview

The GUIX JPEG software decoder enforces no ordering on JPEG markers. A file that places a second `SOF0` frame header after `SOS` re-runs the frame header parser after the output buffer has already been allocated and its geometry latched. The decoder returns `GX_SUCCESS` and publishes a `GX_PIXELMAP` whose reported dimensions and `data_size` exceed the allocation behind it.



Any consumer that trusts the returned structure reads out of bounds, including GUIX's own display drivers, reached through the ordinary draw path.



Reproduces in the shipped default configuration; `GX_SOFTWARE_DECODER_SUPPORT` is enabled by default.

## Affected

- `GUIX <= 6.5.1.202602a`

## Remediation

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