https://cve.radiocsirt.org/rss/recent/all/10 Most recent entries from all 2026-10-04T04:35:48.086080+00:00 Vulnerability-Lookup csirt@opendfir.org python-feedgen Contains only the most 10 recent entries. https://cve.radiocsirt.org/vuln/certfr-2026-avi-0090 certfr-2026-avi-0090 — De multiples vulnérabilités ont été découvertes dans Citrix XenServer. Elles permettent à un attaquant de provoquer un… 2026-10-04T04:35:48.094378+00:00 certfr-2026-avi-0090 https://cve.radiocsirt.org/vuln/euvd-2026-266837 EUVD-2026-266837 2026-10-04T04:35:48.094416+00:00 EUVD-2026-266837 https://cve.radiocsirt.org/vuln/fkie_cve-2026-23553 fkie_cve-2026-23553 2026-10-04T04:35:48.094430+00:00

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 1. 2) vCPU moves to CPU B, idle gets scheduled on A. Xen skips IBPB. 3) On CPU B, guest kernel switches from task 1 to 2, issuing IBPB. 4) vCPU moves back to CPU A. Xen skips IBPB again.

Now, task 2 is running on CPU A with task 1's training still in the BTB.

 https://cve.radiocsirt.org/vuln/ghsa-pxqc-5jg3-xfqm GHSA-pxqc-5jg3-xfqm 2026-10-04T04:35:48.094471+00:00

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 1. 2) vCPU moves to CPU B, idle gets scheduled on A. Xen skips IBPB. 3) On CPU B, guest kernel switches from task 1 to 2, issuing IBPB. 4) vCPU moves back to CPU A. Xen skips IBPB again.

Now, task 2 is running on CPU A with task 1's training still in the BTB.

 https://cve.radiocsirt.org/vuln/opensuse-su-2026:10118-1 openSUSE-SU-2026:10118-1 — xen-4.21.0_04-1.1 on GA media 2026-10-04T04:35:48.094493+00:00

xen-4.21.0_04-1.1 on GA media

 https://cve.radiocsirt.org/vuln/suse-su-2026:0303-1 SUSE-SU-2026:0303-1 — Security update for xen 2026-10-04T04:35:48.094510+00:00

Security update for xen

 https://cve.radiocsirt.org/vuln/ubuntu-cve-2026-23553 UBUNTU-CVE-2026-23553 2026-10-04T04:35:48.094525+00:00

Affected: Ubuntu:16.04:LTS: xen, Ubuntu:18.04:LTS: xen, Ubuntu:20.04:LTS: xen, Ubuntu:22.04:LTS: xen, Ubuntu:24.04:LTS: xen, Ubuntu:25.10: xen, Ubuntu:26.04:LTS: xen

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 1. 2) vCPU moves to CPU B, idle gets scheduled on A. Xen skips IBPB. 3) On CPU B, guest kernel switches from task 1 to 2, issuing IBPB. 4) vCPU moves back to CPU A. Xen skips IBPB again. Now, task 2 is running on CPU A with task 1's training still in the BTB.

 https://cve.radiocsirt.org/vuln/wid-sec-w-2026-0229 WID-SEC-W-2026-0229 — Citrix Systems XenServer und Xen: Schwachstelle ermöglicht Offenlegung von Informationen 2026-10-04T04:35:48.094555+00:00

Ein lokaler Angreifer kann eine Schwachstelle in Citrix Systems XenServer und Xen ausnutzen, um Informationen offenzulegen.