CVE-2026-4426

Libarchive: libarchive: denial of service via malformed iso file processing

publishedCWE-1335

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.

Technical severity6.5 mediumCVSS 3.1 · CNA: redhat

Published2026-03-19Source updated 2026-11-06

Collected2026-11-063 attributed sources

Fixes and workarounds

Workaround

To mitigate this issue, avoid processing untrusted ISO9660 images with `libarchive`. Restricting the sources of ISO files and ensuring they originate from trusted entities can prevent exploitation.

Source: CNA: redhat

Fix

The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.

Source: [email protected]

Affected products and versions

Affected products, source version ranges and reporting authorities
Product	Versions	Authority
Red Hat Hardened Images Red Hat `libarchive-main` https://catalog.redhat.com/software/containers/	≥ 3.8.7-1.hum1; < * (unaffected, rpm) Other versions: affected	CNA: redhat
Red Hat Enterprise Linux 10 Red Hat `libarchive` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: affected	CNA: redhat
Red Hat Enterprise Linux 6 Red Hat `libarchive` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unknown	CNA: redhat
Red Hat Enterprise Linux 7 Red Hat `libarchive` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: affected	CNA: redhat
Red Hat Enterprise Linux 8 Red Hat `libarchive` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: affected	CNA: redhat
Red Hat Enterprise Linux 9 Red Hat `libarchive` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: affected	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-ai-gateway-operator-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-core-bff-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unknown	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-dashboard-operator-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-dashboard-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unknown	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-data-science-pipelines-operator-controller-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-kf-notebook-controller-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unknown	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-kserve-controller-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-kserve-llmisvc-controller-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-kserve-module-operator-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-kuberay-operator-controller-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-kube-rbac-proxy-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-llama-stack-k8s-operator-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-maas-controller-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-mlflow-operator-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-mlflow-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-mod-arch-agent-ops-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unknown	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-mod-arch-automl-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unknown	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-mod-arch-autorag-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unknown	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-mod-arch-eval-hub-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unknown	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-mod-arch-gen-ai-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unknown	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-mod-arch-maas-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unknown	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-mod-arch-mlflow-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unknown	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-mod-arch-model-registry-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unknown	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-model-controller-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-model-registry-operator-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-model-serving-api-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-notebook-controller-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unknown	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-ogx-k8s-operator-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-ogx-module-operator-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-training-operator-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-trustyai-service-operator-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat OpenShift AI (RHOAI) Red Hat `rhoai/odh-workbenches-operator-rhel9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat OpenShift Container Platform 4 Red Hat `openshift/ose-rhel-coreos-8` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: affected	CNA: redhat
Red Hat OpenShift Container Platform 4 Red Hat `openshift/ose-rhel-coreos-9` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: affected	CNA: redhat

Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.

NVD applicability configurations (1)

These expressions retain AND/OR operators, negation, and required environmental products. A listed product is not sufficient to establish exposure when additional conditions apply.

[
  {
    "negate": false,
    "nodes": [
      {
        "cpeMatch": [
          {
            "criteria": "cpe:2.3:a:libarchive:libarchive:-:*:*:*:*:*:*:*",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:a:redhat:hardened_images:-:*:*:*:*:*:*:*",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:a:redhat:openshift_container_platform:4.0:*:*:*:*:*:*:*",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:redhat:enterprise_linux:10.0:*:*:*:*:*:*:*",
            "vulnerable": true
          }
        ],
        "negate": false,
        "operator": "OR"
      }
    ],
    "operator": "OR"
  }
]

CVSS assessments

CVSS scores, vectors and reporting authorities
Version / score	Vector	Authority
3.1 / 6.5 medium	`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H`	CNA: redhat
3.1 / 6.5 medium	`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H`	NVD: [email protected]

Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

References

https://access.redhat.com/errata/RHSA-2026:8944CNA: redhat · vendor-advisory, x_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2026-4426CNA: redhat · vdb-entry, x_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2449010CNA: redhat · issue-tracking, x_refsource_REDHAT
https://github.com/libarchive/libarchive/pull/2897CNA: redhat
https://access.redhat.com/errata/RHSA-2026:8944[email protected]
https://access.redhat.com/security/cve/CVE-2026-4426[email protected] · Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2449010[email protected] · Issue Tracking, Third Party Advisory
https://github.com/libarchive/libarchive/pull/2897[email protected] · Issue Tracking, Patch

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