QEMU-KVM, as used in the Hypervisor (aka rhev-hypervisor) in Red Hat Enterprise Virtualization (RHEV) 2.2 and KVM 83, does not properly validate guest QXL driver pointers, which allows guest OS users to cause a denial of service (invalid pointer dereference and guest OS crash) or possibly gain privileges via unspecified vectors.

Updated rhev-hypervisor packages that fix multiple security issues and two bugs are now available.

The Red Hat Security Response Team has rated this update as having important security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.

The rhev-hypervisor package provides a Red Hat Enterprise Virtualization Hypervisor ISO disk image. The Red Hat Enterprise Virtualization Hypervisor is a dedicated Kernel-based Virtual Machine (KVM) hypervisor. It includes everything necessary to run and manage virtual machines: A subset of the Red Hat Enterprise Linux operating environment and the Red Hat Enterprise Virtualization Agent.

Note: Red Hat Enterprise Virtualization Hypervisor is only available for the Intel 64 and AMD64 architectures with virtualization extensions.

It was found that the libspice component of QEMU-KVM on the host did not validate all pointers provided from a guest system's QXL graphics card driver. A privileged guest user could use this flaw to cause the host to dereference an invalid pointer, causing the guest to crash (denial of service) or, possibly, resulting in the privileged guest user escalating their privileges on the host. (CVE-2010-0428)

It was found that the libspice component of QEMU-KVM on the host could be forced to perform certain memory management operations on memory addresses controlled by a guest. A privileged guest user could use this flaw to crash the guest (denial of service) or, possibly, escalate their privileges on the host. (CVE-2010-0429)

It was found that QEMU-KVM on the host did not validate all pointers provided from a guest system's QXL graphics card driver. A privileged guest user could use this flaw to cause the host to dereference an invalid pointer, causing the guest to crash (denial of service) or, possibly, resulting in the privileged guest user escalating their privileges on the host. (CVE-2010-0431)

A flaw was found in QEMU-KVM, allowing the guest some control over the index used to access the callback array during sub-page MMIO initialization. A privileged guest user could use this flaw to crash the guest (denial of service) or, possibly, escalate their privileges on the host. (CVE-2010-2784)

A NULL pointer dereference flaw was found when Red Hat Enterprise Virtualization Hypervisor was run on a system that has a processor with the Intel VT-x extension enabled. A privileged guest user could use this flaw to trick the host into emulating a certain instruction, which could crash the host (denial of service). (CVE-2010-0435)

A flaw was found in the way VDSM accepted SSL connections. An attacker could trigger this flaw by creating a crafted SSL connection to VDSM, preventing VDSM from accepting SSL connections from other users.
(CVE-2010-2811)

These updated packages provide updated components that include fixes for security issues; however, these issues have no security impact for Red Hat Enterprise Virtualization Hypervisor. These fixes are for avahi issues CVE-2009-0758 and CVE-2010-2244; freetype issues CVE-2010-1797, CVE-2010-2498, CVE-2010-2499, CVE-2010-2500, CVE-2010-2519, CVE-2010-2527, and CVE-2010-2541; kernel issues CVE-2010-1084, CVE-2010-2066, CVE-2010-2070, CVE-2010-2226, CVE-2010-2248, CVE-2010-2521, and CVE-2010-2524; and openldap issues CVE-2010-0211 and CVE-2010-0212.

These updated rhev-hypervisor packages also fix two bugs.
Documentation for these bug fixes will be available shortly from http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Virtualization_fo r_Servers /2.2/html/Technical_Notes/index.html

As Red Hat Enterprise Virtualization Hypervisor is based on KVM, the bug fixes from the KVM update RHSA-2010:0627 have been included in this update. Also included are the bug fixes from the VDSM update RHSA-2010:0628.

KVM: https://rhn.redhat.com/errata/RHSA-2010-0627.html VDSM:
https://rhn.redhat.com/errata/RHSA-2010-0628.html

Users of Red Hat Enterprise Virtualization Hypervisor are advised to upgrade to these updated rhev-hypervisor packages, which resolve these issues.

The remote Oracle Linux 5 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2010-0627 advisory.

    - Resolves: bz#619412       (CVE-2010-2784 qemu: insufficient constraints checking in exec.c:subpage_register() [rhel-5.5.z])
    - kvm-kernel-fix-null-pointer-dereference.patch [bz#570531]
      - Resolves: bz#570531
      - CVE: CVE-2010-0435

Tenable has extracted the preceding description block directly from the Oracle Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Updated kvm packages that fix three security issues and multiple bugs are now available for Red Hat Enterprise Linux 5.

The Red Hat Security Response Team has rated this update as having important security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.

KVM (Kernel-based Virtual Machine) is a full virtualization solution for Linux on AMD64 and Intel 64 systems. KVM is a Linux kernel module built for the standard Red Hat Enterprise Linux kernel.

It was found that QEMU-KVM on the host did not validate all pointers provided from a guest system's QXL graphics card driver. A privileged guest user could use this flaw to cause the host to dereference an invalid pointer, causing the guest to crash (denial of service) or, possibly, resulting in the privileged guest user escalating their privileges on the host. (CVE-2010-0431)

A flaw was found in QEMU-KVM, allowing the guest some control over the index used to access the callback array during sub-page MMIO initialization. A privileged guest user could use this flaw to crash the guest (denial of service) or, possibly, escalate their privileges on the host. (CVE-2010-2784)

A NULL pointer dereference flaw was found when the host system had a processor with the Intel VT-x extension enabled. A privileged guest user could use this flaw to trick the host into emulating a certain instruction, which could crash the host (denial of service).
(CVE-2010-0435)

This update also fixes the following bugs :

* running a 'qemu-img' check on a faulty virtual machine image ended with a segmentation fault. With this update, the segmentation fault no longer occurs when running the 'qemu-img' check. (BZ#610342)

* when attempting to transfer a file between two guests that were joined in the same virtual LAN (VLAN), the receiving guest unexpectedly quit. With this update, the transfer completes successfully. (BZ#610343)

* installation of a system was occasionally failing in KVM. This was caused by KVM using wrong permissions for large guest pages. With this update, the installation completes successfully. (BZ#616796)

* previously, the migration process would fail for a virtual machine because the virtual machine could not map all the memory. This was caused by a conflict that was initiated when a virtual machine was initially run and then migrated right away. With this update, the conflict no longer occurs and the migration process no longer fails.
(BZ#618205)

* using a thinly provisioned VirtIO disk on iSCSI storage and performing a 'qemu-img' check during an 'e_no_space' event returned cluster errors. With this update, the errors no longer appear.
(BZ#618206)

All KVM users should upgrade to these updated packages, which contain backported patches to resolve these issues. Note: The procedure in the Solution section must be performed before this update will take effect.

It was found that QEMU-KVM on the host did not validate all pointers provided from a guest system's QXL graphics card driver. A privileged guest user could use this flaw to cause the host to dereference an invalid pointer, causing the guest to crash (denial of service) or, possibly, resulting in the privileged guest user escalating their privileges on the host. (CVE-2010-0431)

A flaw was found in QEMU-KVM, allowing the guest some control over the index used to access the callback array during sub-page MMIO initialization. A privileged guest user could use this flaw to crash the guest (denial of service) or, possibly, escalate their privileges on the host. (CVE-2010-2784)

A NULL pointer dereference flaw was found when the host system had a processor with the Intel VT-x extension enabled. A privileged guest user could use this flaw to trick the host into emulating a certain instruction, which could crash the host (denial of service).
(CVE-2010-0435)

This update also fixes the following bugs :

  - running a 'qemu-img' check on a faulty virtual machine     image ended with a segmentation fault. With this update,     the segmentation fault no longer occurs when running the     'qemu-img' check. (BZ#610342)

  - when attempting to transfer a file between two guests     that were joined in the same virtual LAN (VLAN), the     receiving guest unexpectedly quit. With this update, the     transfer completes successfully. (BZ#610343)

  - installation of a system was occasionally failing in     KVM. This was caused by KVM using wrong permissions for     large guest pages. With this update, the installation     completes successfully. (BZ#616796)

  - previously, the migration process would fail for a     virtual machine because the virtual machine could not     map all the memory. This was caused by a conflict that     was initiated when a virtual machine was initially run     and then migrated right away. With this update, the     conflict no longer occurs and the migration process no     longer fails. (BZ#618205)

  - using a thinly provisioned VirtIO disk on iSCSI storage     and performing a 'qemu-img' check during an 'e_no_space'     event returned cluster errors. With this update, the     errors no longer appear. (BZ#618206)

NOTE: The following procedure must be performed before this update will take effect :

1) Stop all KVM guest virtual machines.

2) Either reboot the hypervisor machine or, as the root user, remove (using 'modprobe -r [module]') and reload (using 'modprobe [module]') all of the following modules which are currently running (determined using 'lsmod'): kvm, ksm, kvm-intel or kvm-amd.

3) Restart the KVM guest virtual machines.

ID	Name	Product	Family	Severity
79276	RHEL 5 : rhev-hypervisor (RHSA-2010:0622)	Nessus	Red Hat Local Security Checks	medium
68085	Oracle Linux 5 : kvm (ELSA-2010-0627)	Nessus	Oracle Linux Local Security Checks	high
63946	RHEL 5 : kvm (RHSA-2010:0627)	Nessus	Red Hat Local Security Checks	medium
60837	Scientific Linux Security Update : kvm on SL5.x x86_64	Nessus	Scientific Linux Local Security Checks	medium
48910	CentOS 5 : kvm (CESA-2010:0627)	Nessus	CentOS Local Security Checks	medium

Detections

Analytics

CVE-2010-0431

high

Tenable Plugins

medium

high

medium

medium

medium