CVE-2026-90954

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.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-90954
https://bugzilla.redhat.com/show_bug.cgi?id=2533007

Configurations

No configuration.

History

14 Oct 2026, 10:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-14 10:17

Updated : 2026-10-19 20:21

NVD link : CVE-2026-90954

Mitre link : CVE-2026-90954

CVE.ORG link : CVE-2026-90954

JSON object : View

Products Affected

No product.

CWE

CWE-59

Improper Link Resolution Before File Access ('Link Following')

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