CVE-2020-7360

Executive Summary

CVE-2020-7360 is an Uncontrolled Search Path Element (CWE-427) vulnerability in Philips SmartControl, a monitor management utility, affecting version 4.3.15 and earlier releases prior to April 15, 2020. An authenticated local user can exploit this flaw to escalate privileges by placing a specially crafted DLL file in the application's search path, which the application will load with elevated privileges. The vulnerability has a CVSS score of 7.4, indicating high severity, and was addressed in version 1.0.7, released after April 15, 2020.

Technical Analysis

The vulnerability resides in the DLL loading mechanism of Philips SmartControl. SmartControl versions up to and including 4.3.15 suffer from an Uncontrolled Search Path Element vulnerability (CWE-427), which occurs when an application uses a fixed or partially controlled search path to locate and load dynamic-link libraries (DLLs) at runtime.

When the application initializes or performs certain operations, it relies on the Windows DLL search order to locate required libraries. Windows searches directories in a specific sequence: the application directory, the system directory, the Windows directory, the current working directory, and then directories listed in the PATH environment variable. If the application does not explicitly specify an absolute path for DLL loading or fails to sanitize the search path, an attacker can exploit this by placing a malicious DLL in a location that the application will search before reaching the legitimate library.

The attack mechanism works as follows:

1. The application executes with a non-standard DLL search path that includes user-writable directories
2. An authenticated user places a specially crafted DLL file (with a filename matching what the application loads) into a directory earlier in the search order than where the legitimate DLL resides
3. When the application attempts to load the DLL, Windows resolves the search order and loads the attacker's malicious DLL instead
4. The malicious DLL code executes within the security context of the application — if the application runs with elevated privileges, the attacker's code inherits those privileges

The NVD description confirms the vulnerability requires an authenticated user, meaning the attacker must have valid credentials to access the target system. The attack requires local access, as the attacker must place a DLL file on the filesystem. The CVSS score of 7.4 reflects a locally exploitable vulnerability with high impact on confidentiality and integrity, though no impact on availability is noted.

It is important to note that insufficient technical detail is provided in the disclosure regarding which specific DLL files are vulnerable, the exact search path modifications, or which component of SmartControl performs the vulnerable DLL loading. The attack is described at the class level — DLL hijacking via uncontrolled search path — without specifics on the vulnerable function names or the exact DLLs involved.

Exploitation Scenarios

Based on the vulnerability class and available information, the attack chain proceeds as follows:

Step 1: Reconnaissance/Target Identification

• The attacker must first gain authenticated access to a Windows system running Philips SmartControl version 4.3.15 or earlier
• The attacker identifies the presence of SmartControl by checking installed programs, processes running (e.g., monitoring processes), or start-up entries
• The attacker must also identify which directory the application uses for DLL loading and determine write permissions to directories earlier in the search path

Step 2: Flaw Trigger

• The attacker crafts a malicious DLL file that is named identically to a legitimate DLL that SmartControl loads at startup or during specific operations
• The attacker places this crafted DLL in a directory that appears EARLIER in the Windows DLL search order than the legitimate DLL location
• Since the application does not enforce a strict, controlled search path, it will inadvertently load the attacker's DLL when the application starts or performs the relevant operation

Step 3: Payload Execution

• When SmartControl launches (either automatically at startup or when manually invoked), Windows resolves the DLL search order and loads the malicious DLL presented by the attacker
• The attacker's code in the DLL's entry point (e.g., DllMain) executes automatically when loaded
• The code runs with the privileges of the SmartControl process — if the application runs in the context of an administrator service or with elevated integrity, the attacker's code inherits those elevated privileges

Step 4: Post-Exploitation

• The executed code performs arbitrary actions with elevated privileges, potentially including creation of new administrator accounts, disabling security software, exfiltration of sensitive data, or installation of persistent backdoors
• The attacker achieves privilege escalation from a standard authenticated user to a higher-privileged context

No public PoC is available for this vulnerability; the attack chain is inferred from the vulnerability class (CWE-427 DLL hijacking). The lack of public exploit code does not diminish the risk, as DLL hijacking techniques are well-documented and can be adapted by attackers with basic proficiency.

Impact Assessment

The CVSS score of 7.4 (high severity) with a vector indicating Local, High complexity, Low privileges, No user interaction, and Changed scope underscores the risk:

• Confidentiality (High): An attacker can execute code with elevated privileges, allowing access to sensitive data readable by the application's context
• Integrity (High): Arbitrary code execution permits modification of system files, registry settings, and other integrity-sensitive components
• Availability (None): The vulnerability does not inherently cause denial of service, though an attacker could intentionally disrupt availability post-exploitation
• Privilege Escalation: The primary impact is elevation from an authenticated standard user to a higher-privileged context
• Scoped Impact (Changed): The compromised component (SmartControl) affects assets beyond its security scope — code execution may affect the broader operating system

The business impact is significant for organizations using Philips display management software in enterprise deployments. Blast radius includes any workstation where SmartControl is installed. The vulnerability could serve as a stepping stone in a multi-stage attack, enabling lateral movement or persistence. The EPSS score of 0.00487 (39.5th percentile) suggests low current exploitation probability, but this metric reflects known active exploitation and does not account for future weaponization.

Detection Guidance

Sigma Rule

title: Potential Philips SmartControl DLL Hijacking Attempt
id: 4f8ac3d1-9b7e-4a3c-8f2d-1e5b6c7d8e9f
status: experimental
description: Detects file creation events in directories that could be used for DLL hijacking against Philips SmartControl, particularly non-standard DLL files placed in user-writable paths
author: Valtersit Threat Intelligence
date: 2024/01/15
tags:
    - attack.privilege_escalation
    - attack.t1574.001
    - cve.2020-7360
logsource:
    category: file_event
    product: windows
detection:
    selection:
        EventID: 11  # FileCreate
        TargetFilename|endswith: '.dll'
        TargetFilename|contains:
            - 'C:\Users\'
            - 'C:\ProgramData\'
            - 'C:\Windows\Temp\'
    filter_smartcontrol_dir:
        TargetFilename|contains: 'SmartControl'
    condition: selection and filter_smartcontrol_dir
falsepositives:
    - Legitimate DLL updates to SmartControl
    - Software installation processes
level: high

YARA Rule

rule Philips_SmartControl_DLL_Hijack_Indicators
{
    meta:
        author = "Valtersit Threat Intelligence"
        date = "2024-01-15"
        description = "Detects potential malicious DLLs targeting Philips SmartControl"
        cve = "CVE-2020-7360"
        severity = "high"
    strings:
        $smart_control_str1 = "SmartControl" ascii wide nocase
        $smart_control_str2 = "Philips Monitor" ascii wide nocase
        $dll_marker = "MZ" ascii
        $export_func = "DllMain" ascii wide
    condition:
        uint16(0) == 0x5A4D and  // MZ header
        $dll_marker at 0 and
        (($smart_control_str1 or $smart_control_str2) or
        (filesize < 500KB and $export_func))
}

Suricata IDS Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"CVE-2020-7360 Philips SmartControl DLL Hijacking - Possible DLL Download"; flow:established,to_server; content:"GET"; http_method; content:"|2e|dll|3f|"; http_uri; nocase; content:"smartcontrol"; http_uri; nocase; threshold:type limit, track by_src, count 1, seconds 60; classtype:attempted-privilege-grant; sid:2020073601; rev:1; metadata:created_at 2024_01_15, updated_at 2024_01_15, cve CVE-2020-7360;)

Note: Given the local nature of this vulnerability, network detection is limited. The above rule targets scenarios where a compromised host attempts to download a DLL from an external source, potentially as part of a hijacking campaign.

Elastic Detection

sequence by host.name with maxspan=30s
  [file where event.action == "creation"
   and file.extension == "dll"
   and file.path : ("C:\\Users\\*", "C:\\ProgramData\\*", "C:\\Windows\\Temp\\*")
   and process.name : "SmartControl*"] // Adjust process name based on environment

Splunk SPL Query

index=windows sourcetype=WinEventLog:Security OR sourcetype="XmlWinEventLog"
(EventCode=4663 OR EventCode=11)
| search Object_Name="*.dll"
| search Object_Name="C:\\Users\\*" OR Object_Name="C:\\ProgramData\\*" OR Object_Name="C:\\Windows\\Temp\\*"
| search Object_Name="*SmartControl*" OR (process_name="*SmartControl*")
| table _time, host, process_name, user, Object_Name, Action
| sort - _time

Wazuh OSSEC Rule

<group name="philips_smartcontrol,">
  <rule id="100360" level="12">
    <if_sid>550</if_sid>
    <field name="file">\.dll$</field>
    <regex>\.dll</regex>
    <description>Potential Philips SmartControl DLL hijacking - DLL file activity in user-writable locations</description>
    <group>windows,sysmon,eventmonitor,</group>
    <var name="TARGET_DLLS">SmartControl|Philips</var>
  </rule>
</group>

Mitigation & Patch Guidance

Patch Confidence: 0/4 — UNPATCHED — No patch evidence from any tracked source was identified. The vendor has not published a security advisory or patch bulletin in accessible channels.

Immediate Mitigations (in order of priority):

1. Upgrade SmartControl: Update Philips SmartControl to version 1.0.7 or later (released after April 15, 2020). This is the only known remediation that addresses the vulnerability directly.
2. Restrict Installation: Remove SmartControl from systems where it is not essential to business operations. This reduces the attack surface entirely.
3. Apply Least Privilege: Ensure SmartControl processes do not run with administrative/elevated privileges. If feasible, run the application under a standard user context to limit the impact of a successful exploit.
4. Harden File System Permissions: Restrict write access to directories in the DLL search path (particularly user-writable directories) using NTFS ACLs. This prevents authenticated users from placing malicious DLLs.
5. Implement Application Whitelisting: Deploy application control policies (e.g., Windows Defender Application Control, AppLocker) to block loading of unsigned or non-approved DLLs.

Long-Term Hardening:

• Monitor vendor communications for a confirmed patch status — given the 0/4 patch confidence, treat this vulnerability as unpatched until the vendor confirms otherwise
• Implement DLL load monitoring in enterprise SIEM/SOAR platforms to detect anomalous library loading behavior
• Maintain a comprehensive asset inventory to identify all systems running SmartControl and prioritize their patching once a fix becomes available
• Integrate CVE-2020-7360 into vulnerability management workflows with the CVSS 7.4 score as the risk basis

References

1. NVD Entry: https://nvd.nist.gov/vuln/detail/CVE-2020-7360
2. MITRE CWE-427: https://cwe.mitre.org/data/definitions/427.html — Uncontrolled Search Path Element, the root weakness class
3. MITRE ATT&CK Technique T1574: https://attack.mitre.org/techniques/T1574/ — Hijack Execution Flow, including sub-technique T1574.001 (DLL Search Order Hijacking)
4. EPSS (Exploit Prediction Scoring System): https://www.first.org/epss/ — Reference for EPSS score 0.00487, 39.5th percentile
5. CISA Known Exploited Vulnerabilities Catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog — CVE-2020-7360 is NOT listed, indicating no confirmed exploitation in the wild at the time of this report

Threat Actor Activity: No known threat actor campaigns have been publicly attributed to exploitation of CVE-2020-7360. No exploit code has been disclosed in public repositories, and the vulnerability is not present in the CISA KEV catalog. However, the DLL hijacking technique is a common post-exploitation method observed in multiple threat actor toolkits, and unpatched systems remain at elevated risk should weaponized exploit code be released.