---
id: CVE-2026-92449
title: >-
  Binary resource loader: unbounded map_id from a theme file causes a heap
  out-of-bounds write in the GUIX-allocated arena
summary: >-
  `_gx_binres_pixelmap_table_load()` in the GUIX binary resource (theme) loader
  indexes the pixelmap table with a value read verbatim from the resource file
  and never bounds it against the table size. A crafted theme drives a write of
  up t…
severity: medium
cvss: 6.8
cvssVector: 'CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:L/VI:H/VA:H/SC:N/SI:N/SA:N'
cvssSource: cna
cwe:
  - CWE-129
  - CWE-457
  - CWE-787
vendor: Eclipse Foundation
product: GUIX
affected:
  - GUIX >= 6.3.0 <= 6.5.1.202602a
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-20T15:27:16.562385Z'
published: '2026-10-20'
updated: '2026-10-20'
sourceUpdated: '2026-10-20T15:27:55.848Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-92449'
references:
  - url: >-
      https://github.com/eclipse-threadx/guix/security/advisories/GHSA-m85v-2ccm-w6gf
tags:
  - cve.org
ingestedAt: '2026-10-20T15:09:24.113Z'
---

## Overview

`_gx_binres_pixelmap_table_load()` in the GUIX binary resource (theme) loader indexes the pixelmap table with a value read verbatim from the resource file and never bounds it against the table size. A crafted theme drives a write of up to roughly 256 KB past the end of the table.



The overflowed buffer is allocated by GUIX itself, through `_gx_system_memory_allocator`, rather than supplied by the caller, so the loader corrupts its own arena. The public API `gx_binres_theme_load()` takes no size parameter, so no amount of caller diligence prevents this.



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

## Affected

- `GUIX >= 6.3.0 <= 6.5.1.202602a`

## Remediation

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