Fedora: Security Advisory (FEDORA-2026-844012d662)

The remote host is missing an update for the SPDX-FileCopyrightText: 2026 Greenbone AG Some text descriptions might be excerpted from a referenced sources, and are Copyright C by the respective right holders. SPDX-License-Identifier: GPL-2.0-only ifdescription...

xen-4.21.0_04-1.1 on GA media (moderate)

xen-4.21.004-1.1 on GA media Announcement ID: openSUSE-SU-2026:10118-1 Rating: moderate Cross-References: CVE-2025-58150 CVE-2026-23553 CVSS scores: CVE-2025-58150 SUSE : 5.3 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L CVE-2025-58150 SUSE : 4.8...

CVE-2026-23553

In the context switch logic Xen attempts to skip an IBPB in the case of a vCPU returning to a CPU on which it was the previous vCPU to run. While safe for Xen's isolation between vCPUs, this prevents the guest kernel correctly isolating between tasks. Consider: 1 vCPU runs on CPU A, running task ...

CVE-2026-23553

In the context switch logic Xen attempts to skip an IBPB in the case of a vCPU returning to a CPU on which it was the previous vCPU to run. While safe for Xen's isolation between vCPUs, this prevents the guest kernel correctly isolating between tasks. Consider: 1 vCPU runs on CPU A, running task ...

Security update for xen

This update for xen fixes the following issues: CVE-2025-58150: Fixed buffer overrun with shadow paging and tracing XSA-477 bsc1256745 CVE-2026-23553: Fixed incomplete IBPB for vCPU isolation XSA-479 bsc1256747 Special Instructions and Notes: Please reboot the system after installing this update...