CVE-2026-4426 — MEDIUM (6.5)

Vulnerability 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.

CVSS Score

6.5

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

REQUIRED

Scope

UNCHANGED

Confidentiality

NONE

Integrity

NONE

Availability

HIGH

Affected Products

Vendor	Product	Versions
Libarchive	Libarchive	-
Redhat	Hardened Images	-
Redhat	Openshift Container Platform	4.0
Redhat	Enterprise Linux	6.0

Related Weaknesses (CWE)

CWE-1335

References

https://access.redhat.com/errata/RHSA-2026:8944
https://access.redhat.com/security/cve/CVE-2026-4426Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2449010Issue TrackingThird Party Advisory
https://github.com/libarchive/libarchive/pull/2897Issue TrackingPatch

FAQ

What is CVE-2026-4426?

CVE-2026-4426 is a vulnerability with a CVSS score of 6.5 (MEDIUM). 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 exten...

How severe is CVE-2026-4426?

CVE-2026-4426 has been rated MEDIUM with a CVSS base score of 6.5/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-4426?

Check the references section above for vendor advisories and patch information. Affected products include: Libarchive Libarchive, Redhat Hardened Images, Redhat Openshift Container Platform, Redhat Enterprise Linux.