CVE-2022-49042: Synology Hyper Backup Explorer RCE Flaw

CVE-2022-49042 Overview

CVE-2022-49042 is a local code execution vulnerability in the MinGW DLL component of Synology Hyper Backup Explorer. The flaw stems from inclusion of functionality from an untrusted control sphere [CWE-829], allowing local users to execute arbitrary code through unspecified vectors. Synology addressed the issue in Hyper Backup Explorer version 3.0.1-0156.

The vulnerability requires local access with low privileges and no user interaction. Successful exploitation yields high impact on confidentiality, integrity, and availability of the affected host.

Critical Impact
Local attackers can execute arbitrary code in the context of the user running Hyper Backup Explorer, enabling privilege abuse and full host compromise.

Affected Products

Synology Hyper Backup Explorer versions prior to 3.0.1-0156
MinGW DLL component bundled with Hyper Backup Explorer
Windows hosts running the vulnerable Hyper Backup Explorer build

Discovery Timeline

2026-06-03 - CVE-2022-49042 published to NVD
2026-06-03 - Last updated in NVD database

Technical Details for CVE-2022-49042

Vulnerability Analysis

The vulnerability is classified under [CWE-829]: Inclusion of Functionality from Untrusted Control Sphere. Synology Hyper Backup Explorer loads MinGW DLL components without sufficiently constraining the source of those libraries. When the application resolves a DLL dependency, it can load a library placed in a directory writable by a local user.

The loaded code executes within the process space of Hyper Backup Explorer. This grants the attacker the same privileges as the user running the application. The MinGW runtime DLLs shipped with the product expand the set of libraries that can be hijacked compared to a standalone binary.

Root Cause

The root cause is insecure DLL search order handling within the Hyper Backup Explorer process. The application does not pin DLL resolution to a trusted directory or validate the integrity of loaded modules. Attackers exploit this by placing a malicious DLL with a matching name in a location that precedes the legitimate library in the search order.

Attack Vector

Exploitation requires local access to the system with low privileges. A local user stages a malicious DLL where Hyper Backup Explorer searches for MinGW runtime components. When a legitimate user launches the application, the planted DLL is loaded and its code runs in that user's context.

The vulnerability mechanism is described in prose only. No verified public proof-of-concept code is available. Refer to the Synology Release Notes for vendor guidance.

Detection Methods for CVE-2022-49042

Indicators of Compromise

Unexpected .dll files (for example libgcc_s_dw2-1.dll, libstdc++-6.dll, libwinpthread-1.dll) located in user-writable directories alongside HyperBackupExplorer.exe.
Hyper Backup Explorer process spawning unexpected child processes such as cmd.exe, powershell.exe, or rundll32.exe.
Module loads from non-standard paths into the Hyper Backup Explorer process.

Detection Strategies

Monitor for LoadLibrary and image-load events targeting MinGW runtime DLLs from paths outside the installation directory.
Hash-verify MinGW DLLs shipped with Hyper Backup Explorer against known-good values from the vendor.
Alert on file writes of DLL files into directories that contain HyperBackupExplorer.exe by non-administrative users.

Monitoring Recommendations

Enable Windows Sysmon Event ID 7 (Image Loaded) on hosts where Hyper Backup Explorer is installed.
Track installed versions of Hyper Backup Explorer across the fleet and flag any build earlier than 3.0.1-0156.
Review endpoint telemetry for anomalous process trees originating from Hyper Backup Explorer.

How to Mitigate CVE-2022-49042

Immediate Actions Required

Upgrade Synology Hyper Backup Explorer to version 3.0.1-0156 or later on all Windows hosts.
Inventory endpoints to identify users running vulnerable builds, including portable installations.
Restrict write permissions on directories containing HyperBackupExplorer.exe to administrators only.

Patch Information

Synology fixed the issue in Hyper Backup Explorer 3.0.1-0156. Download the updated installer from the Synology Release Notes and redeploy across affected workstations.

Workarounds

Run Hyper Backup Explorer only from trusted, write-protected directories such as C:\Program Files\.
Avoid launching Hyper Backup Explorer from removable media, shared folders, or user download directories.
Apply AppLocker or Windows Defender Application Control policies to restrict DLL loading to signed, trusted publishers.

bash

# Configuration example: verify installed version on Windows
powershell -Command "Get-ItemProperty 'HKLM:\Software\Microsoft\Windows\CurrentVersion\Uninstall\*' | Where-Object { $_.DisplayName -like 'Hyper Backup Explorer*' } | Select-Object DisplayName, DisplayVersion"