CVE-2026-90954 (GCVE-0-2026-90954)

Vulnerability from cvelistv5 – Published: 2026-10-14 10:00 – Updated: 2026-10-14 10:00
VLAI
Title
Busybox: busybox: dpkg-deb extraction-root escape via per-ar-member deferred symlink flush
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 .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.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CWE
  • CWE-59 - Improper Link Resolution Before File Access ('Link Following')
Assigner
redhat CNA under the redhat root
CNA scorecard B 82/100 over 1021 records in the last 180 days details
References
URL Tags
https://access.redhat.com/security/cve/CVE-2026-90954 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2533007 issue-trackingx_refsource_REDHAT
Impacted products
Vendor Product Version CPE status
Red Hat Red Hat Hardened Images     cpe:/a:redhat:hummingbird:1
Create a notification for this product.
Date Public
2026-10-14 08:00
Credits
Red Hat would like to thank Shubham Raj (Causal Security) for reporting this issue.
Show details on NVD website
To clipboard 

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      "source": "Red Hat CSAF VEX",
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      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-90954.json",
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}



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