---
id: CVE-2026-90954
title: A flaw was found in BusyBox's dpkg-deb archive extraction
summary: >-
  A flaw was found in BusyBox's dpkg-deb archive extraction. The ar archive
  handler flushes deferred symlinks after each archive member, unlike the tar,
  cpio, and unzip handlers which flush once after the last member. A specially
  crafted .…
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'
cwe:
  - CWE-59
published: '2026-10-14'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T10:17:57.297'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-90954'
references:
  - url: 'https://access.redhat.com/security/cve/CVE-2026-90954'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2533007'
    label: secalert@redhat.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-90954.json
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-90954'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-90954'
tags:
  - nvd
  - csaf
  - vex
  - red-hat
ingestedAt: '2026-10-14T10:25:41.203Z'
vendor: Red Hat
product: Red Hat Hardened Images
affected:
  - hardened_images
---

## Overview

A flaw was found in BusyBox's dpkg-deb archive extraction. The ar archive handler flushes deferred symlinks after each archive member, unlike the tar, cpio, and unzip handlers which flush once after the last member. A specially crafted .deb archive with two data.tar members can exploit this ordering: the first member declares a symlink pointing to an absolute path (e.g., '/'), which is deferred as unsafe but flushed after the first member. The second member declares a regular file whose path traverses the now-live symlink, resulting in a file being written outside the intended extraction directory. This could allow an attacker to write arbitrary files to arbitrary locations when a user extracts a crafted .deb package.

## Remediation

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

## Vendor advisories

- **Red Hat VEX** · Important · affected: Red Hat Hardened Images · no fix planned: Red Hat Hardened Images · updated 2026-10-14 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-90954.json)