Xen Project Hypervisor versions 4.3.4 and 4.4.2 are available

I am pleased to announce the release of Xen 4.3.4 and Xen 4.4.2. Both releases are available immediately from their git repositories and download pages (see below). We recommend to all users of the 4.3 and 4.4 stable series to update to these latest point releases.

Xen 4.3.4

This release is available immediately from its git repository at
http://xenbits.xen.org/gitweb/?p=xen.git;a=shortlog;h=refs/heads/stable-4.3
(tag RELEASE-4.3.4) or from the XenProject download page.

Note that this is expected to be the last release of the 4.3 stable series. The tree will be switched to security only maintenance mode after this release.

This fixes the following critical vulnerabilities:

  • CVE-2014-5146, CVE-2014-5149 / XSA-97: Long latency virtual-mmu operations are not preemptible
  • CVE-2014-7154 / XSA-104: Race condition in HVMOP_track_dirty_vram
  • CVE-2014-7155 / XSA-105: Missing privilege level checks in x86 HLT, LGDT, LIDT, and LMSW emulation
  • CVE-2014-7156 / XSA-106: Missing privilege level checks in x86 emulation of software interrupts
  • CVE-2014-7188 / XSA-108: Improper MSR range used for x2APIC emulation
  • CVE-2014-8594 / XSA-109: Insufficient restrictions on certain MMU update hypercalls
  • CVE-2014-8595 / XSA-110: Missing privilege level checks in x86 emulation of far branches
  • CVE-2014-8866 / XSA-111: Excessive checking in compatibility mode hypercall argument translation
  • CVE-2014-8867 / XSA-112: Insufficient bounding of “REP MOVS” to MMIO emulated inside the hypervisor
  • CVE-2014-9030 / XSA-113: Guest effectable page reference leak in MMU_MACHPHYS_UPDATE handling
  • CVE-2014-9065, CVE-2014-9066 / XSA-114: p2m lock starvation
  • CVE-2015-0361 / XSA-116: xen crash due to use after free on hvm guest teardown
  • CVE-2015-1563 / XSA-118: arm: vgic: incorrect rate limiting of guest triggered logging
  • CVE-2015-2152 / XSA-119: HVM qemu unexpectedly enabling emulated VGA graphics backends
  • CVE-2015-2044 / XSA-121: Information leak via internal x86 system device emulation
  • CVE-2015-2045 / XSA-122: Information leak through version information hypercall
  • CVE-2015-2151 / XSA-123: Hypervisor memory corruption due to x86 emulator flaw

Additionally a bug in the fix for CVE-2014-3969 / CVE-2015-2290 / XSA-98 (which got assigned CVE-2015-2290) got addressed.

Sadly the workaround for CVE-2013-3495 / XSA-59 (Intel VT-d Interrupt Remapping engines can be evaded by native NMI interrupts) still can’t be guaranteed to cover all affected chipsets; Intel continues to be working on providing us with a complete list.

Apart from those there are many further bug fixes and improvements.

We recommend all users of the 4.3 stable series to update to this last point release.

Xen 4.4.2

This release is available immediately from its git repository at
http://xenbits.xen.org/gitweb/?p=xen.git;a=shortlog;h=refs/heads/stable-4.4
(tag RELEASE-4.4.2) or from the XenProject download page.

This fixes the following critical vulnerabilities:

  • CVE-2014-5146, CVE-2014-5149 / XSA-97: Long latency virtual-mmu operations are not preemptible
  • CVE-2014-7154 / XSA-104: Race condition in HVMOP_track_dirty_vram
  • CVE-2014-7155 / XSA-105: Missing privilege level checks in x86 HLT, LGDT, LIDT, and LMSW emulation
  • CVE-2014-7156 / XSA-106: Missing privilege level checks in x86 emulation of software interrupts
  • CVE-2014-6268 / XSA-107: Mishandling of uninitialised FIFO-based event channel control blocks
  • CVE-2014-7188 / XSA-108: Improper MSR range used for x2APIC emulation
  • CVE-2014-8594 / XSA-109: Insufficient restrictions on certain MMU update hypercalls
  • CVE-2014-8595 / XSA-110: Missing privilege level checks in x86 emulation of far branches
  • CVE-2014-8866 / XSA-111: Excessive checking in compatibility mode hypercall argument translation
  • CVE-2014-8867 / XSA-112: Insufficient bounding of “REP MOVS” to MMIO emulated inside the hypervisor
  • CVE-2014-9030 / XSA-113: Guest effectable page reference leak in MMU_MACHPHYS_UPDATE handling
  • CVE-2014-9065, CVE-2014-9066 / XSA-114: p2m lock starvation
  • CVE-2015-0361 / XSA-116: xen crash due to use after free on hvm guest teardown
  • CVE-2015-1563 / XSA-118: arm: vgic: incorrect rate limiting of guest triggered logging
  • CVE-2015-2152 / XSA-119: HVM qemu unexpectedly enabling emulated VGA graphics backends
  • CVE-2015-2044 / XSA-121: Information leak via internal x86 system device emulation
  • CVE-2015-2045 / XSA-122: Information leak through version information hypercall
  • CVE-2015-2151 / XSA-123: Hypervisor memory corruption due to x86 emulator flaw

Additionally a bug in the fix for CVE-2014-3969 / CVE-2015-2290 / XSA-98 (which got assigned CVE-2015-2290) got addressed.

Sadly the workaround for CVE-2013-3495 / XSA-59 (Intel VT-d Interrupt Remapping engines can be evaded by native NMI interrupts) still can’t be guaranteed to cover all affected chipsets; Intel continues to be working on providing us with a complete list.

Apart from those there are many further bug fixes and improvements.

We recommend all users of the 4.4 stable series to update to this first point release.

Read more

🛠️ Xen Summit 2025: Find Your Place in the Future of Virtualization
06/27/2025

The annual Xen Summit is right around the corner, and there has never been a more exciting time to be part of the Xen Project. As enterprise and industrial needs shift and proprietary vendors rethink their licensing, the industry is ready for strong, open alternatives. Xen stands out not only

Let’s Grow Xen Together!
03/18/2025

Xen is open, secure, and built for the future. As the new Community Manager, I’m focused on growing the Xen community, welcoming new contributors, and ensuring a thriving ecosystem. Let’s build the future of virtualization together!

Xen Project 4.20: A Step Forward in Open Source Virtualization
03/11/2025

The Xen Project has released Xen 4.20 🎉! This release introduces a range of enhancements that further solidify its position as the premier open-source hypervisor. It delivers important security updates, improved performance, and broader hardware support. Xen has doubled down as the best choice for cloud providers, enterprise users, and

Xen Project Winter Meetup
02/13/2025

We just wrapped up the Xen Winter Meetup 2025. It was an amazing opportunity to push Xen forward in a way that can only happen when people get together in person. Organized by Vates, we hosted it at the University of Grenoble IMAG building, a great spot for cutting-edge research