CVE-2025-27466

[This CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] There are multiple issues related to the handling and accessing of guest memory pages in the viridian code: 1. A NULL pointer dereference in the updating of the reference TSC area. This is CVE-2025-27466. 2. A NULL pointer dereference by assuming the SIM page is mapped when a synthetic timer message has to be delivered. This is CVE-2025-58142. 3. A race in the mapping of the reference TSC page, where a guest can get Xen to free a page while still present in the guest physical to machine (p2m) page tables. This is CVE-2025-58143.

[This CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] There are multiple issues related to the handling and accessing of guest memory pages in the viridian code: 1. A NULL pointer dereference in the updating of the reference TSC area. This is CVE-2025-27466. 2. A NULL pointer dereference by assuming the SIM page is mapped when a synthetic timer message has to be delivered. This is CVE-2025-58142. 3. A race in the mapping of the reference TSC page, where a guest can get Xen to free a page while still present in the guest physical to machine (p2m) page tables. This is CVE-2025-58143.

Double unlock in x86 guest IRQ handling. (CVE-2024-31143) Xapi: Metadata injection attack against backup/restore functionality. (CVE-2024-31144) Error handling in x86 IOMMU identity mapping. (CVE-2024-31145) PCI device pass-through with shared resources. (CVE-2024-31146) x86: Deadlock in vlapic_error(). (CVE-2024-45817) Deadlock in x86 HVM standard VGA handling. (CVE-2024-45818) libxl leaks data to PVH guests via ACPI tables. (CVE-2024-45819) Backend can crash Linux netfront. (CVE-2024-53240) Xen hypercall page unsafe against speculative attacks. (CVE-2024-53241) Deadlock potential with VT-d and legacy PCI device pass-through. (CVE-2025-1713) x86: Indirect Target Selection. (CVE-2024-28956) x86: Incorrect stubs exception handling for flags recovery. (CVE-2025-27465) TSA-SQ (TSA in the Store Queues). (CVE-2024-36350) TSA-L1 (TSA in the L1 data cache). (CVE-2024-36357) A NULL pointer dereference in the updating of the reference TSC area. (CVE-2025-27466) A NULL pointer dereference by assuming the SIM page is mapped when a synthetic timer message has to be delivered. (CVE-2025-58142) A race in the mapping of the reference TSC page, where a guest can get Xen to free a page while still present in the guest physical to machine (p2m) page tables. (CVE-2025-58143) An assertion is wrong there, where the case actually needs handling. A NULL pointer de-reference could result on a release build. (CVE-2025-58144) The P2M lock isn't held until a page reference was actually obtained (or the attempt to do so has failed). Otherwise the page can not only change type, but even ownership in between, thus allowing domain boundaries to be violated. (CVE-2025-58145) XAPI UTF-8 string handling. (CVE-2025-58146) Hypercalls using the HV_VP_SET Sparse format can cause vpmask_set() to write out of bounds when converting the bitmap to Xen's format. (CVE-2025-58147) Hypercalls using any input format can cause send_ipi() to read d->vcpu[] out-of-bounds, and operate on a wild vCPU pointer.(CVE-2025-58148) Incorrect removal of permissions on PCI device unplug. (CVE-2025-58149)

These are all security issues fixed in the xen-4.20.1_04-1.1 package on the GA media of openSUSE Tumbleweed.

This update for xen fixes the following issues:

Security issues fixed:

• CVE-2025-27466: NULL pointer dereference in the Viridian interface when updating the reference TSC area (bsc#1248807).
• CVE-2025-58142: NULL pointer dereference in the Viridian interface due to assumption that the SIM page is mapped when a synthetic timer message has to be delivered (bsc#1248807).
• CVE-2025-58143: information leak and reference counter underflow in the Viridian interface due to race in the mapping of the reference TSC page (bsc#1248807).

Other issues fixed:

• efi: Call FreePages() only if needed (bsc#1027519).
• x86/hpet: do local APIC EOI after interrupt processing (bsc#1027519).
• x86/hvm/ioreq: Fix condition in hvm_alloc_legacy_ioreq_gfn() (bsc#1027519).
• x86/idle: Fix the C6 eoi_errata[] list to include NEHALEM_EX (bsc#1027519).
• x86/iommu: setup MMCFG ahead of IOMMU (bsc#1027519).
• x86/mce: Adjustments to intel_init_ppin() (bsc#1027519).
• x86/mkelf32: pad load segment to 2Mb boundary (bsc#1027519).

This update for xen fixes the following issues:

• CVE-2025-58147, CVE-2025-58148: Fixed incorrect input sanitisation in Viridian hypercalls (bsc#1251271, XSA-475)
• CVE-2025-27466, CVE-2025-58142, CVE-2025-58143: Fixed mutiple vulnerabilities in the Viridian interface (bsc#1248807, XSA-472)

This update for xen fixes the following issues:

• CVE-2025-58147, CVE-2025-58148: Fixed incorrect input sanitisation in Viridian hypercalls (bsc#1251271, XSA-475)
• CVE-2025-27466, CVE-2025-58142, CVE-2025-58143: Fixed mutiple vulnerabilities in the Viridian interface (bsc#1248807, XSA-472)

This update for xen fixes the following issues:

• CVE-2025-58147, CVE-2025-58148: Fixed incorrect input sanitisation in Viridian hypercalls (bsc#1251271, XSA-475)
• CVE-2025-27466, CVE-2025-58142, CVE-2025-58143: Fixed mutiple vulnerabilities in the Viridian interface (bsc#1248807, XSA-472)

This update for xen fixes the following issues:

Security issues fixed:

• CVE-2025-27466: NULL pointer dereference in the Viridian interface when updating the reference TSC area (bsc#1248807).
• CVE-2025-58142: NULL pointer dereference in the Viridian interface due to assumption that the SIM page is mapped when a synthetic timer message has to be delivered (bsc#1248807).
• CVE-2025-58143: information leak and reference counter underflow in the Viridian interface due to race in the mapping of the reference TSC page (bsc#1248807).
• CVE-2025-58147: incorrect input sanitisation in Viridian hypercalls using the HV_VP_SET Sparse format can lead to out-of-bounds write through vpmask_set() (bsc#1251271).
• CVE-2025-58148: incorrect input sanitisation in Viridian hypercalls using any input format can lead to out-of-bounds read through send_ipi() (bsc#1251271).
• CVE-2025-58149: incorrect removal of permissions on PCI device unplug allows PV guests to access memory of devices no longer assigned to them (bsc#1252692).

Other issues fixed:

• Several upstream bug fixes (bsc#1027519).
• Failure to restart xenstored (bsc#1254180).

This update for xen fixes the following issues:

Security fixes:

• CVE-2025-58150: Fixed buffer overrun with shadow paging and tracing (XSA-477) (bsc#1256745)
• CVE-2026-23553: Fixed incomplete IBPB for vCPU isolation (XSA-479) (bsc#1256747)
• CVE-2025-58149: Fixed incorrect removal od permissions on PCI device unplug allow PV guests to access memory of devices no longer assigned to it (XSA-476) (bsc#1252692)
• CVE-2025-27466, CVE-2025-58142, CVE-2025-58143: Fixed multiple vulnerabilities in the Viridian interface (XSA-472) (bsc#1248807)

Other fixes:

• Fixed virtxend service restart. Caused by a failure to start xenstored (bsc#1254180)