CVE-2016-7084 : Detail

CVE-2016-7084

7.8
/
High
Overflow
0.12%V3
Local
2016-12-29
08h02 +00:00
2017-09-02
07h57 +00:00
CVE.org
NVD
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CVE Descriptions

tpview.dll in VMware Workstation Pro 12.x before 12.5.0 and VMware Workstation Player 12.x before 12.5.0 on Windows, when Cortado ThinPrint virtual printing is enabled, allows guest OS users to execute arbitrary code on the host OS or cause a denial of service (host OS memory corruption) via a JPEG 2000 image.

CVE Informations

Related Weaknesses

CWE-ID Weakness Name Source
CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer
The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.

Metrics

Metrics Score Severity CVSS Vector Source
V3.0 7.8 HIGH CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H

Base: Exploitabilty Metrics

The Exploitability metrics reflect the characteristics of the thing that is vulnerable, which we refer to formally as the vulnerable component.

Attack Vector

This metric reflects the context by which vulnerability exploitation is possible.

Local

A vulnerability exploitable with Local access means that the vulnerable component is not bound to the network stack, and the attacker's path is via read/write/execute capabilities. In some cases, the attacker may be logged in locally in order to exploit the vulnerability, otherwise, she may rely on User Interaction to execute a malicious file.

Attack Complexity

This metric describes the conditions beyond the attacker's control that must exist in order to exploit the vulnerability.

High

A successful attack depends on conditions beyond the attacker's control. That is, a successful attack cannot be accomplished at will, but requires the attacker to invest in some measurable amount of effort in preparation or execution against the vulnerable component before a successful attack can be expected.

Privileges Required

This metric describes the level of privileges an attacker must possess before successfully exploiting the vulnerability.

Low

The attacker is authorized with (i.e. requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.

User Interaction

This metric captures the requirement for a user, other than the attacker, to participate in the successful compromise of the vulnerable component.

None

The vulnerable system can be exploited without interaction from any user.

Base: Scope Metrics

An important property captured by CVSS v3.0 is the ability for a vulnerability in one software component to impact resources beyond its means, or privileges.

Scope

Formally, Scope refers to the collection of privileges defined by a computing authority (e.g. an application, an operating system, or a sandbox environment) when granting access to computing resources (e.g. files, CPU, memory, etc). These privileges are assigned based on some method of identification and authorization. In some cases, the authorization may be simple or loosely controlled based upon predefined rules or standards. For example, in the case of Ethernet traffic sent to a network switch, the switch accepts traffic that arrives on its ports and is an authority that controls the traffic flow to other switch ports.

Changed

An exploited vulnerability can affect resources beyond the authorization privileges intended by the vulnerable component. In this case the vulnerable component and the impacted component are different.

Base: Impact Metrics

The Impact metrics refer to the properties of the impacted component.

Confidentiality Impact

This metric measures the impact to the confidentiality of the information resources managed by a software component due to a successfully exploited vulnerability.

High

There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact. For example, an attacker steals the administrator's password, or private encryption keys of a web server.

Integrity Impact

This metric measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of information.

High

There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.

Availability Impact

This metric measures the impact to the availability of the impacted component resulting from a successfully exploited vulnerability.

High

There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Temporal Metrics

The Temporal metrics measure the current state of exploit techniques or code availability, the existence of any patches or workarounds, or the confidence that one has in the description of a vulnerability.

Environmental Metrics

 nvd@nist.gov
V2 6.9 AV:L/AC:M/Au:N/C:C/I:C/A:C nvd@nist.gov

EPSS

EPSS is a scoring model that predicts the likelihood of a vulnerability being exploited.

EPSS Score

The EPSS model produces a probability score between 0 and 1 (0 and 100%). The higher the score, the greater the probability that a vulnerability will be exploited.

EPSS Percentile

The percentile is used to rank CVE according to their EPSS score. For example, a CVE in the 95th percentile according to its EPSS score is more likely to be exploited than 95% of other CVE. Thus, the percentile is used to compare the EPSS score of a CVE with that of other CVE.
EPSS First.org

Exploit information

Exploit Database EDB-ID : 40399

Publication date : 2016-09-18 22h00 +00:00
Author : Google Security Research
EDB Verified : Yes

Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=850 As already discussed in a number of reports in this tracker (#285, #286, #287, #288, #289, #292), VMware Workstation (current version 12.1.1 build-3770994) ships with a feature called "Virtual Printers", which enables the virtualized operating systems to access printers installed on the Host. Inside the VM, the communication takes place through a COM1 device, and the incoming data is handled by a dedicated "vprintproxy.exe" process on the Host, as launched by the "vmware-vmx.exe" service. Administrative privileges are not required to access COM1 in the guest, at least on Windows. The vprintproxy.exe is a significant attack surface for potential VM escapes. Due to its nature, the application implements support for a variety of complex protocols and file formats, such as the printing protocol, EMFSPOOL format, and further embedded EMFs, fonts, images etc. This report addresses a multitude of bugs in the handling of JPEG2000 images embedded in a custom record 0x8000 inside EMF, as implemented in the TPView.DLL library extensively used by vprintproxy.exe. The version of the TPView.DLL file referenced in this report is 9.4.1045.1 (md5sum b6211e8b5c2883fa16231b0a6bf014f3). The CTPViewDoc::WriteEMF function (adddress 0x100518F0) iterates over all EMF records found in the EMFSPOOL structure sent over COM1 for printing, and performs special handling of some of them. One such record is a custom type 0x8000, expected to store a JPEG2000 image wrapped in a structure similar to that of a EMF_STRETCHDIBITS record. The handler at 0x100516A0, and more specifically a further nested function at 0x1003C000 performs complete parsing of the J2K format, opening up the potential for software vulnerabilities. An example of a bug in that code area discovered in the past is a stack-based buffer overflow in the processing of record 0xff5c (Quantization Default), reported by Kostya Kortchinsky in bug #287. Since the source code of the JPEG2000 implementation used by VMware is not publicly available, and the file format is sufficiently complex that a manual audit sounds like a dire and very ineffective option to find bugs, I have set up a fuzzing session to automate the process. As a result, with the PageHeap option enabled in Application Verifier for vprintproxy.exe, the fuzzer has managed to trigger hundreds of crashes, in a total of 39 unique code locations. Below is a list of different instructions which generated a crash, with a brief description of the underlying reason. +----------------------------+-----------------------------------------------+ | Instruction | Reason | +----------------------------+-----------------------------------------------+ | add [eax+edx*4], edi | Heap buffer overflow | | cmp [eax+0x440], ebx | Heap out-of-bounds read | | cmp [eax+0x8], esi | Heap out-of-bounds read | | cmp [edi+0x70], ebx | Heap out-of-bounds read | | cmp [edi], edx | Heap out-of-bounds read | | cmp dword [eax+ebx*4], 0x0 | Heap out-of-bounds read | | cmp dword [esi+eax*4], 0x0 | Heap out-of-bounds read | | div dword [ebp-0x24] | Division by zero | | div dword [ebp-0x28] | Division by zero | | fld dword [edi] | NULL pointer dereference | | idiv ebx | Division by zero | | idiv edi | Division by zero | | imul ebx, [edx+eax+0x468] | Heap out-of-bounds read | | mov [eax-0x4], edx | Heap buffer overflow | | mov [ebx+edx*8], eax | Heap buffer overflow | | mov [ecx+edx], eax | Heap buffer overflow | | mov al, [esi] | Heap out-of-bounds read | | mov bx, [eax] | NULL pointer dereference | | mov eax, [ecx] | NULL pointer dereference | | mov eax, [edi+ecx+0x7c] | Heap out-of-bounds read | | mov eax, [edx+0x7c] | Heap out-of-bounds read | | movdqa [edi], xmm0 | Heap buffer overflow | | movq mm0, [eax] | NULL pointer dereference | | movq mm1, [ebx] | NULL pointer dereference | | movq mm2, [edx] | NULL pointer dereference | | movzx eax, byte [ecx-0x1] | Heap out-of-bounds read | | movzx eax, byte [edx-0x1] | Heap out-of-bounds read | | movzx ebx, byte [eax+ecx] | Heap out-of-bounds read | | movzx ecx, byte [esi+0x1] | Heap out-of-bounds read | | movzx ecx, byte [esi] | Heap out-of-bounds read | | movzx edi, word [ecx] | NULL pointer dereference | | movzx esi, word [edx] | NULL pointer dereference | | push dword [ebp-0x8] | Stack overflow (deep / infinite recursion) | | push ebp | Stack overflow (deep / infinite recursion) | | push ebx | Stack overflow (deep / infinite recursion) | | push ecx | Stack overflow (deep / infinite recursion) | | push edi | Stack overflow (deep / infinite recursion) | | push esi | Stack overflow (deep / infinite recursion) | | rep movsd | Heap buffer overflow, Heap out-of-bounds read | +----------------------------+-----------------------------------------------+ Considering the volume of the crashes, I don't have the resources to investigate the root cause of each of them, and potentially deduplicate the list even further. My gut feeling is that the entirety of the crashes may represent 10 or more different bugs in the code. Attached is a Python script which can be used to test each particular JPEG2000 sample: it is responsible for wrapping it in the corresponding EMF + EMFSPOOL structures and sending to the COM1 serial port on the guest system. It is a reworked version of Kostya's original exploit from bug #287. In the same ZIP archive, you can also find up to three samples per each crash site listed above. It was empirically confirmed that some of the heap corruptions can be leveraged to achieve arbitrary code execution, as when the Page Heap mechanism was disabled, the process would occasionally crash at invalid EIP or a CALL instruction referencing invalid memory addresses (vtables). Proof of Concept: https://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/40399.zip

Products Mentioned

Configuraton 0

Vmware>>Workstation_player >> Version 12.0.0

Vmware>>Workstation_player >> Version 12.0.1

Vmware>>Workstation_player >> Version 12.1.0

Vmware>>Workstation_player >> Version 12.1.1

Vmware>>Workstation_pro >> Version 12.0.0

Vmware>>Workstation_pro >> Version 12.0.1

Vmware>>Workstation_pro >> Version 12.1.0

Vmware>>Workstation_pro >> Version 12.1.1

Microsoft>>Windows >> Version *

References

https://www.exploit-db.com/exploits/40399/
Tags : exploit, x_refsource_EXPLOIT-DB
http://www.securitytracker.com/id/1036805
Tags : vdb-entry, x_refsource_SECTRACK
http://www.securityfocus.com/bid/92934
Tags : vdb-entry, x_refsource_BID