Red Hat Security Advisory

RHSA-2026:75863

OpenShift Virtualization v4.21 Images

Released 2026-10-05 · Red Hat rating Important · View on Red Hat →

Fixed in

Red Hat Container Native Virtualization 4.21 registry.redhat.io/container-native-virtualization/kubemacpool-rhel9

Fixes 3 records

TI-2026-40997 CVE-2026-56859 · GHSA-76p8-fhrm-vpc7

Add recursion depth guard during decode in encoding/xml

MEDIUM 40

Previously, DecodeElement would reset the depth counter causing it to never fire; this could lead to stack exhaustion.

CVSS 3.1HIGH 7.5 Network No auth No interaction EPSS 0.00568 Published 2026-08-13 Partial fix · 1.25.13, 1.26.6 +1 CWE-770

TI-2026-40998 CVE-2026-56860 · GHSA-25mv-j2qr-v5jq

Avoid quadratic complexity in resolvePath in net/url

LOW 27

Previously, resolving relative paths containing parent directory ('..') segments performed string conversions and buffer rewrites on each step, resulting in quadratic time complexity and high memory allocation overhead.

CVSS 3.1MEDIUM 5.9 Network No auth No interaction EPSS 0.0055 Published 2026-08-13 Partial fix · 1.25.13, 1.26.6 +1 CWE-407

TI-2026-40996 CVE-2026-56858 · GHSA-c974-w86c-vpfw

Fix Javascript regexp context tracking in html/template

LOW 27

Previously, pathological inputs could close an unescaped '/' early, allowing for attack-controlled data to inject arbitrary content, potentially leading to XSS.

CVSS 3.1MEDIUM 6.1 Network No auth User interaction EPSS 0.0031 Published 2026-08-13 Partial fix · 1.25.13, 1.26.6 +1 CWE-79