Vulnerability record/PUBLISHED/Published Mar 19, 2026 13:53:39 UTC

CVE-2026-4426

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.

Base score6.5/ 10

SeverityMediumCVSS 3.1

Exploitability / impact

CVSS metric breakdown

Vector-derived attributes

Base severityMedium

Attack vectorNetworkAV

Attack complexityLowAC

Privileges requiredNonePR

User interactionRequiredUI

ScopeUnchangedS

Confidentiality impactNoneC

Integrity impactNoneI

Availability impactHighA

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

CVSS communicates standardized severity and impact characteristics. It does not establish whether a system is exploitable in your specific environment.

Record context

CVE Numbering Authorityredhat

Last updatedNov 6, 2026 07:52:00 UTC

PublishedMar 19, 2026 13:53:39 UTC

ReservedMar 19, 2026 12:43:31 UTC

Credits

Red Hat would like to thank Elhanan Haenel for reporting this issue.