Vulnerabilities > CVE-2016-4963 - Improper Access Control vulnerability in XEN
Attack vector
LOCAL Attack complexity
HIGH Privileges required
LOW Confidentiality impact
NONE Integrity impact
NONE Availability impact
HIGH Summary
The libxl device-handling in Xen through 4.6.x allows local guest OS users with access to the driver domain to cause a denial of service (management tool confusion) by manipulating information in the backend directories in xenstore.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Embedding Scripts within Scripts An attack of this type exploits a programs' vulnerabilities that are brought on by allowing remote hosts to execute scripts. The attacker leverages this capability to execute scripts to execute his/her own script by embedding it within other scripts that the target software is likely to execute. The attacker must have the ability to inject script into script that is likely to be executed. If this is done, then the attacker can potentially launch a variety of probes and attacks against the web server's local environment, in many cases the so-called DMZ, back end resources the web server can communicate with, and other hosts. With the proliferation of intermediaries, such as Web App Firewalls, network devices, and even printers having JVMs and Web servers, there are many locales where an attacker can inject malicious scripts. Since this attack pattern defines scripts within scripts, there are likely privileges to execute said attack on the host. Of course, these attacks are not solely limited to the server side, client side scripts like Ajax and client side JavaScript can contain malicious scripts as well. In general all that is required is for there to be sufficient privileges to execute a script, but not protected against writing.
- Signature Spoofing by Key Theft An attacker obtains an authoritative or reputable signer's private signature key by theft and then uses this key to forge signatures from the original signer to mislead a victim into performing actions that benefit the attacker.
Nessus
NASL family SuSE Local Security Checks NASL id SUSE_SU-2016-2533-1.NASL description This update for xen fixes several issues. These security issues were fixed : - CVE-2014-3672: The qemu implementation in libvirt Xen allowed local guest OS users to cause a denial of service (host disk consumption) by writing to stdout or stderr (bsc#981264). - CVE-2016-3158: The xrstor function did not properly handle writes to the hardware FSW.ES bit when running on AMD64 processors, which allowed local guest OS users to obtain sensitive register content information from another guest by leveraging pending exception and mask bits (bsc#973188). - CVE-2016-3159: The fpu_fxrstor function in arch/x86/i387.c did not properly handle writes to the hardware FSW.ES bit when running on AMD64 processors, which allowed local guest OS users to obtain sensitive register content information from another guest by leveraging pending exception and mask bits (bsc#973188). - CVE-2016-3710: The VGA module improperly performed bounds checking on banked access to video memory, which allowed local guest OS administrators to execute arbitrary code on the host by changing access modes after setting the bank register, aka the last seen 2020-06-01 modified 2020-06-02 plugin id 94269 published 2016-10-26 reporter This script is Copyright (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/94269 title SUSE SLES12 Security Update : xen (SUSE-SU-2016:2533-1) (Bunker Buster) NASL family Debian Local Security Checks NASL id DEBIAN_DLA-1493.NASL description Multiple vulnerabilities have been discovered in the Xen hypervisor, which could result in denial of service, informations leaks or privilege escalation. For Debian 8 last seen 2020-06-01 modified 2020-06-02 plugin id 117349 published 2018-09-07 reporter This script is Copyright (C) 2018 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/117349 title Debian DLA-1493-1 : xen security update NASL family Fedora Local Security Checks NASL id FEDORA_2016-103752D2A9.NASL description Qemu: scsi: esp: OOB r/w access while processing ESP_FIFO [CVE-2016-5338] (#1343323) Qemu: scsi: megasas: information leakage in megasas_ctrl_get_info [CVE-2016-5337] (#1343909) ---- fix for CVE-2016-2858 doesn last seen 2020-06-05 modified 2016-07-14 plugin id 92059 published 2016-07-14 reporter This script is Copyright (C) 2016-2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/92059 title Fedora 23 : xen (2016-103752d2a9) NASL family FreeBSD Local Security Checks NASL id FREEBSD_PKG_E589AE90421211E6942DBC5FF45D0F28.NASL description The Xen Project reports : libxl last seen 2020-06-01 modified 2020-06-02 plugin id 91937 published 2016-07-05 reporter This script is Copyright (C) 2016-2018 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/91937 title FreeBSD : xen-tools -- Unsanitised driver domain input in libxl device handling (e589ae90-4212-11e6-942d-bc5ff45d0f28) NASL family Fedora Local Security Checks NASL id FEDORA_2016-389BE30B95.NASL description fix for CVE-2016-2858 doesn last seen 2020-06-05 modified 2016-07-14 plugin id 92081 published 2016-07-14 reporter This script is Copyright (C) 2016-2020 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/92081 title Fedora 24 : xen (2016-389be30b95) NASL family SuSE Local Security Checks NASL id SUSE_SU-2016-2093-1.NASL description This update for xen to version 4.5.3 fixes the several issues. These security issues were fixed : - CVE-2016-6258: Potential privilege escalation in PV guests (XSA-182) (bsc#988675). - CVE-2016-6259: Missing SMAP whitelisting in 32-bit exception / event delivery (XSA-183) (bsc#988676). - CVE-2016-5337: The megasas_ctrl_get_info function allowed local guest OS administrators to obtain sensitive host memory information via vectors related to reading device control information (bsc#983973). - CVE-2016-5338: The (1) esp_reg_read and (2) esp_reg_write functions allowed local guest OS administrators to cause a denial of service (QEMU process crash) or execute arbitrary code on the host via vectors related to the information transfer buffer (bsc#983984). - CVE-2016-5238: The get_cmd function in hw/scsi/esp.c might have allowed local guest OS administrators to cause a denial of service (out-of-bounds write and QEMU process crash) via vectors related to reading from the information transfer buffer in non-DMA mode (bsc#982960). - CVE-2016-4453: The vmsvga_fifo_run function allowed local guest OS administrators to cause a denial of service (infinite loop and QEMU process crash) via a VGA command (bsc#982225). - CVE-2016-4454: The vmsvga_fifo_read_raw function allowed local guest OS administrators to obtain sensitive host memory information or cause a denial of service (QEMU process crash) by changing FIFO registers and issuing a VGA command, which triggered an out-of-bounds read (bsc#982224). - CVE-2016-5126: Heap-based buffer overflow in the iscsi_aio_ioctl function allowed local guest OS users to cause a denial of service (QEMU process crash) or possibly execute arbitrary code via a crafted iSCSI asynchronous I/O ioctl call (bsc#982286). - CVE-2016-5105: Stack information leakage while reading configuration (bsc#982024). - CVE-2016-5106: Out-of-bounds write while setting controller properties (bsc#982025). - CVE-2016-5107: Out-of-bounds read in megasas_lookup_frame() function (bsc#982026). - CVE-2016-4963: The libxl device-handling allowed local guest OS users with access to the driver domain to cause a denial of service (management tool confusion) by manipulating information in the backend directories in xenstore (bsc#979670). - CVE-2016-4962: The libxl device-handling allowed local OS guest administrators to cause a denial of service (resource consumption or management facility confusion) or gain host OS privileges by manipulating information in guest controlled areas of xenstore (bsc#979620). - CVE-2016-4952: Out-of-bounds access issue in pvsci_ring_init_msg/data routines (bsc#981276). - CVE-2014-3672: The qemu implementation in libvirt Xen allowed local guest OS users to cause a denial of service (host disk consumption) by writing to stdout or stderr (bsc#981264). - CVE-2016-4441: The get_cmd function in the 53C9X Fast SCSI Controller (FSC) support did not properly check DMA length, which allowed local guest OS administrators to cause a denial of service (out-of-bounds write and QEMU process crash) via unspecified vectors, involving an SCSI command (bsc#980724). - CVE-2016-4439: The esp_reg_write function in the 53C9X Fast SCSI Controller (FSC) support did not properly check command buffer length, which allowed local guest OS administrators to cause a denial of service (out-of-bounds write and QEMU process crash) or potentially execute arbitrary code on the host via unspecified vectors (bsc#980716). - CVE-2016-3710: The VGA module improperly performed bounds checking on banked access to video memory, which allowed local guest OS administrators to execute arbitrary code on the host by changing access modes after setting the bank register, aka the last seen 2020-06-01 modified 2020-06-02 plugin id 93296 published 2016-09-02 reporter This script is Copyright (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/93296 title SUSE SLED12 / SLES12 Security Update : xen (SUSE-SU-2016:2093-1) (Bunker Buster) NASL family SuSE Local Security Checks NASL id SUSE_SU-2016-2100-1.NASL description This update for xen fixes the several issues. These security issues were fixed : - CVE-2014-3672: The qemu implementation in libvirt Xen allowed local guest OS users to cause a denial of service (host disk consumption) by writing to stdout or stderr (bsc#981264). - CVE-2016-3158: The xrstor function did not properly handle writes to the hardware FSW.ES bit when running on AMD64 processors, which allowed local guest OS users to obtain sensitive register content information from another guest by leveraging pending exception and mask bits (bsc#973188). - CVE-2016-3159: The fpu_fxrstor function in arch/x86/i387.c did not properly handle writes to the hardware FSW.ES bit when running on AMD64 processors, which allowed local guest OS users to obtain sensitive register content information from another guest by leveraging pending exception and mask bits (bsc#973188). - CVE-2016-3710: The VGA module improperly performed bounds checking on banked access to video memory, which allowed local guest OS administrators to execute arbitrary code on the host by changing access modes after setting the bank register, aka the last seen 2020-06-01 modified 2020-06-02 plugin id 93298 published 2016-09-02 reporter This script is Copyright (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof. source https://www.tenable.com/plugins/nessus/93298 title SUSE SLES11 Security Update : xen (SUSE-SU-2016:2100-1) (Bunker Buster) NASL family SuSE Local Security Checks NASL id OPENSUSE-2016-1169.NASL description This update for xen fixes the following issues : These security issues were fixed : - CVE-2016-7092: The get_page_from_l3e function in arch/x86/mm.c in Xen allowed local 32-bit PV guest OS administrators to gain host OS privileges via vectors related to L3 recursive pagetables (bsc#995785) - CVE-2016-7093: Xen allowed local HVM guest OS administrators to overwrite hypervisor memory and consequently gain host OS privileges by leveraging mishandling of instruction pointer truncation during emulation (bsc#995789) - CVE-2016-7094: Buffer overflow in Xen allowed local x86 HVM guest OS administrators on guests running with shadow paging to cause a denial of service via a pagetable update (bsc#995792) - CVE-2016-7154: Use-after-free vulnerability in the FIFO event channel code in Xen allowed local guest OS administrators to cause a denial of service (host crash) and possibly execute arbitrary code or obtain sensitive information via an invalid guest frame number (bsc#997731) - CVE-2016-6836: VMWARE VMXNET3 NIC device support was leaging information leakage. A privileged user inside guest could have used this to leak host memory bytes to a guest (boo#994761) - CVE-2016-6888: Integer overflow in packet initialisation in VMXNET3 device driver. A privileged user inside guest could have used this flaw to crash the Qemu instance resulting in DoS (bsc#994772) - CVE-2016-6833: Use-after-free issue in the VMWARE VMXNET3 NIC device support. A privileged user inside guest could have used this issue to crash the Qemu instance resulting in DoS (boo#994775) - CVE-2016-6835: Buffer overflow in the VMWARE VMXNET3 NIC device support, causing an OOB read access (bsc#994625) - CVE-2016-6834: A infinite loop during packet fragmentation in the VMWARE VMXNET3 NIC device support allowed privileged user inside guest to crash the Qemu instance resulting in DoS (bsc#994421) - CVE-2016-6258: The PV pagetable code in arch/x86/mm.c in Xen allowed local 32-bit PV guest OS administrators to gain host OS privileges by leveraging fast-paths for updating pagetable entries (bsc#988675) - CVE-2016-5403: The virtqueue_pop function in hw/virtio/virtio.c in QEMU allowed local guest OS administrators to cause a denial of service (memory consumption and QEMU process crash) by submitting requests without waiting for completion (boo#990923) - CVE-2016-6351: The esp_do_dma function in hw/scsi/esp.c, when built with ESP/NCR53C9x controller emulation support, allowed local guest OS administrators to cause a denial of service (out-of-bounds write and QEMU process crash) or execute arbitrary code on the host via vectors involving DMA read into ESP command buffer (bsc#990843) - CVE-2016-6258: The PV pagetable code in arch/x86/mm.c in Xen allowed local 32-bit PV guest OS administrators to gain host OS privileges by leveraging fast-paths for updating pagetable entries (bsc#988675) - CVE-2016-5337: The megasas_ctrl_get_info function in hw/scsi/megasas.c in QEMU allowed local guest OS administrators to obtain sensitive host memory information via vectors related to reading device control information (bsc#983973) - CVE-2016-5338: The (1) esp_reg_read and (2) esp_reg_write functions in hw/scsi/esp.c in QEMU allowed local guest OS administrators to cause a denial of service (QEMU process crash) or execute arbitrary code on the QEMU host via vectors related to the information transfer buffer (bsc#983984) - CVE-2016-5238: The get_cmd function in hw/scsi/esp.c in QEMU allowed local guest OS administrators to cause a denial of service (out-of-bounds write and QEMU process crash) via vectors related to reading from the information transfer buffer in non-DMA mode (bsc#982960) - CVE-2016-4453: The vmsvga_fifo_run function in hw/display/vmware_vga.c in QEMU allowed local guest OS administrators to cause a denial of service (infinite loop and QEMU process crash) via a VGA command (bsc#982225) - CVE-2016-4454: The vmsvga_fifo_read_raw function in hw/display/vmware_vga.c in QEMU allowed local guest OS administrators to obtain sensitive host memory information or cause a denial of service (QEMU process crash) by changing FIFO registers and issuing a VGA command, which triggers an out-of-bounds read (bsc#982224) - CVE-2016-5126: Heap-based buffer overflow in the iscsi_aio_ioctl function in block/iscsi.c in QEMU allowed local guest OS users to cause a denial of service (QEMU process crash) or possibly execute arbitrary code via a crafted iSCSI asynchronous I/O ioctl call (bsc#982286) - CVE-2016-5105: The megasas_dcmd_cfg_read function in hw/scsi/megasas.c in QEMU, when built with MegaRAID SAS 8708EM2 Host Bus Adapter emulation support, used an uninitialized variable, which allowed local guest administrators to read host memory via vectors involving a MegaRAID Firmware Interface (MFI) command (bsc#982024) - CVE-2016-5106: The megasas_dcmd_set_properties function in hw/scsi/megasas.c in QEMU, when built with MegaRAID SAS 8708EM2 Host Bus Adapter emulation support, allowed local guest administrators to cause a denial of service (out-of-bounds write access) via vectors involving a MegaRAID Firmware Interface (MFI) command (bsc#982025) - CVE-2016-5107: The megasas_lookup_frame function in QEMU, when built with MegaRAID SAS 8708EM2 Host Bus Adapter emulation support, allowed local guest OS administrators to cause a denial of service (out-of-bounds read and crash) via unspecified vectors (bsc#982026) - CVE-2016-4963: The libxl device-handling allowed local guest OS users with access to the driver domain to cause a denial of service (management tool confusion) by manipulating information in the backend directories in xenstore (bsc#979670) - CVE-2016-4962: The libxl device-handling allowed local OS guest administrators to cause a denial of service (resource consumption or management facility confusion) or gain host OS privileges by manipulating information in guest controlled areas of xenstore (bsc#979620) - CVE-2016-4952: Out-of-bounds access issue in pvsci_ring_init_msg/data routines (bsc#981276) - CVE-2014-3672: The qemu implementation in libvirt Xen allowed local guest OS users to cause a denial of service (host disk consumption) by writing to stdout or stderr (bsc#981264) - CVE-2016-4441: The get_cmd function in the 53C9X Fast SCSI Controller (FSC) support did not properly check DMA length, which allowed local guest OS administrators to cause a denial of service (out-of-bounds write and QEMU process crash) via unspecified vectors, involving an SCSI command (bsc#980724) - CVE-2016-4439: The esp_reg_write function in the 53C9X Fast SCSI Controller (FSC) support did not properly check command buffer length, which allowed local guest OS administrators to cause a denial of service (out-of-bounds write and QEMU process crash) or potentially execute arbitrary code on the host via unspecified vectors (bsc#980716) - CVE-2016-3710: The VGA module improperly performed bounds checking on banked access to video memory, which allowed local guest OS administrators to execute arbitrary code on the host by changing access modes after setting the bank register, aka the last seen 2020-06-05 modified 2016-10-12 plugin id 93999 published 2016-10-12 reporter This script is Copyright (C) 2016-2020 Tenable Network Security, Inc. source https://www.tenable.com/plugins/nessus/93999 title openSUSE Security Update : xen (openSUSE-2016-1169) (Bunker Buster) NASL family SuSE Local Security Checks NASL id OPENSUSE-2016-1170.NASL description This update for xen fixes the following issues : These security issues were fixed : - CVE-2016-7092: The get_page_from_l3e function in arch/x86/mm.c in Xen allowed local 32-bit PV guest OS administrators to gain host OS privileges via vectors related to L3 recursive pagetables (bsc#995785) - CVE-2016-7093: Xen allowed local HVM guest OS administrators to overwrite hypervisor memory and consequently gain host OS privileges by leveraging mishandling of instruction pointer truncation during emulation (bsc#995789) - CVE-2016-7094: Buffer overflow in Xen allowed local x86 HVM guest OS administrators on guests running with shadow paging to cause a denial of service via a pagetable update (bsc#995792) - CVE-2016-6836: VMWARE VMXNET3 NIC device support was leaging information leakage. A privileged user inside guest could have used this to leak host memory bytes to a guest (boo#994761) - CVE-2016-6888: Integer overflow in packet initialisation in VMXNET3 device driver. A privileged user inside guest could have used this flaw to crash the Qemu instance resulting in DoS (bsc#994772) - CVE-2016-6833: Use-after-free issue in the VMWARE VMXNET3 NIC device support. A privileged user inside guest could have used this issue to crash the Qemu instance resulting in DoS (boo#994775) - CVE-2016-6835: Buffer overflow in the VMWARE VMXNET3 NIC device support, causing an OOB read access (bsc#994625) - CVE-2016-6834: A infinite loop during packet fragmentation in the VMWARE VMXNET3 NIC device support allowed privileged user inside guest to crash the Qemu instance resulting in DoS (bsc#994421) - CVE-2016-6258: The PV pagetable code in arch/x86/mm.c in Xen allowed local 32-bit PV guest OS administrators to gain host OS privileges by leveraging fast-paths for updating pagetable entries (bsc#988675) - CVE-2016-6259: Xen did not implement Supervisor Mode Access Prevention (SMAP) whitelisting in 32-bit exception and event delivery, which allowed local 32-bit PV guest OS kernels to cause a denial of service (hypervisor and VM crash) by triggering a safety check (bsc#988676) - CVE-2016-5403: The virtqueue_pop function in hw/virtio/virtio.c in QEMU allowed local guest OS administrators to cause a denial of service (memory consumption and QEMU process crash) by submitting requests without waiting for completion (boo#990923) - CVE-2016-6351: The esp_do_dma function in hw/scsi/esp.c, when built with ESP/NCR53C9x controller emulation support, allowed local guest OS administrators to cause a denial of service (out-of-bounds write and QEMU process crash) or execute arbitrary code on the host via vectors involving DMA read into ESP command buffer (bsc#990843) - CVE-2016-6258: The PV pagetable code in arch/x86/mm.c in Xen allowed local 32-bit PV guest OS administrators to gain host OS privileges by leveraging fast-paths for updating pagetable entries (bsc#988675) - CVE-2016-6259: Xen did not implement Supervisor Mode Access Prevention (SMAP) whitelisting in 32-bit exception and event delivery, which allowed local 32-bit PV guest OS kernels to cause a denial of service (hypervisor and VM crash) by triggering a safety check (bsc#988676) - CVE-2016-5337: The megasas_ctrl_get_info function in hw/scsi/megasas.c in QEMU allowed local guest OS administrators to obtain sensitive host memory information via vectors related to reading device control information (bsc#983973) - CVE-2016-5338: The (1) esp_reg_read and (2) esp_reg_write functions in hw/scsi/esp.c in QEMU allowed local guest OS administrators to cause a denial of service (QEMU process crash) or execute arbitrary code on the QEMU host via vectors related to the information transfer buffer (bsc#983984) - CVE-2016-5238: The get_cmd function in hw/scsi/esp.c in QEMU allowed local guest OS administrators to cause a denial of service (out-of-bounds write and QEMU process crash) via vectors related to reading from the information transfer buffer in non-DMA mode (bsc#982960) - CVE-2016-4453: The vmsvga_fifo_run function in hw/display/vmware_vga.c in QEMU allowed local guest OS administrators to cause a denial of service (infinite loop and QEMU process crash) via a VGA command (bsc#982225) - CVE-2016-4454: The vmsvga_fifo_read_raw function in hw/display/vmware_vga.c in QEMU allowed local guest OS administrators to obtain sensitive host memory information or cause a denial of service (QEMU process crash) by changing FIFO registers and issuing a VGA command, which triggers an out-of-bounds read (bsc#982224) - CVE-2016-5126: Heap-based buffer overflow in the iscsi_aio_ioctl function in block/iscsi.c in QEMU allowed local guest OS users to cause a denial of service (QEMU process crash) or possibly execute arbitrary code via a crafted iSCSI asynchronous I/O ioctl call (bsc#982286) - CVE-2016-5105: The megasas_dcmd_cfg_read function in hw/scsi/megasas.c in QEMU, when built with MegaRAID SAS 8708EM2 Host Bus Adapter emulation support, used an uninitialized variable, which allowed local guest administrators to read host memory via vectors involving a MegaRAID Firmware Interface (MFI) command (bsc#982024) - CVE-2016-5106: The megasas_dcmd_set_properties function in hw/scsi/megasas.c in QEMU, when built with MegaRAID SAS 8708EM2 Host Bus Adapter emulation support, allowed local guest administrators to cause a denial of service (out-of-bounds write access) via vectors involving a MegaRAID Firmware Interface (MFI) command (bsc#982025) - CVE-2016-5107: The megasas_lookup_frame function in QEMU, when built with MegaRAID SAS 8708EM2 Host Bus Adapter emulation support, allowed local guest OS administrators to cause a denial of service (out-of-bounds read and crash) via unspecified vectors (bsc#982026) - CVE-2016-4963: The libxl device-handling allowed local guest OS users with access to the driver domain to cause a denial of service (management tool confusion) by manipulating information in the backend directories in xenstore (bsc#979670) - CVE-2016-4962: The libxl device-handling allowed local OS guest administrators to cause a denial of service (resource consumption or management facility confusion) or gain host OS privileges by manipulating information in guest controlled areas of xenstore (bsc#979620) - CVE-2016-4952: Out-of-bounds access issue in pvsci_ring_init_msg/data routines (bsc#981276) - CVE-2016-3710: The VGA module improperly performed bounds checking on banked access to video memory, which allowed local guest OS administrators to execute arbitrary code on the host by changing access modes after setting the bank register, aka the last seen 2020-06-05 modified 2016-10-12 plugin id 94000 published 2016-10-12 reporter This script is Copyright (C) 2016-2020 Tenable Network Security, Inc. source https://www.tenable.com/plugins/nessus/94000 title openSUSE Security Update : xen (openSUSE-2016-1170) (Bunker Buster)