CVE-2026-4426

Publication date 19 March 2026

Last updated 13 May 2026


Ubuntu priority

Cvss 3 Severity Score

6.5 · Medium

Score breakdown

Description

A flaw was found in libarchive. An Undefined Behavior vulnerability exists in the zisofs decompression logic, caused by improper validation of a field (`pz_log2_bs`) read from ISO9660 Rock Ridge extensions. A remote attacker can exploit this by supplying a specially crafted ISO file. This can lead to incorrect memory allocation and potential application crashes, resulting in a denial-of-service (DoS) condition.

Status

Package Ubuntu Release Status
libarchive 26.04 LTS resolute
Vulnerable
25.10 questing
Vulnerable
24.04 LTS noble
Vulnerable
22.04 LTS jammy
Vulnerable
20.04 LTS focal
Vulnerable
18.04 LTS bionic
Vulnerable
16.04 LTS xenial
Vulnerable
14.04 LTS trusty
Vulnerable

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
libarchive

Severity score breakdown

Parameter Value
Base score 6.5 · Medium
Attack vector Network
Attack complexity Low
Privileges required None
User interaction Required
Scope Unchanged
Confidentiality None
Integrity impact None
Availability impact High
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

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