Diagram illustrating Notepad++ DLL hijacking attack: malicious NppExport.dll replacement in plugins folder, proxying to original DLL, code execution flow upon app launch, with icons for Windows search paths, message box PoC, and mitigation shields like mo

A newly disclosed DLL hijacking vulnerability in Notepad++, tracked as CVE-2025-56383, affects version 8.8.3 and likely all installed versions, exposing millions of users to arbitrary code execution. Local attackers can plant a malicious DLL in a directory searched by the app before legitimate ones, such as in the plugins folder for NppExport.dll. This flaw exploits Windows' DLL loading mechanism, allowing persistence or privilege escalation once initial access is gained via malware or phishing.

Diagram illustrating Notepad++ DLL hijacking attack: malicious NppExport.dll replacement in plugins folder, proxying to original DLL, code execution flow upon app launch, with icons for Windows search paths, message box PoC, and mitigation shields like moDiagram illustrating Notepad++ DLL hijacking attack: malicious NppExport.dll replacement in plugins folder, proxying to original DLL, code execution flow upon app launch, with icons for Windows search paths, message box PoC, and mitigation shields like mo

A proof-of-concept exploit demonstrates replacing NppExport.dll with a malicious version that proxies calls to the renamed original (e.g., original-NppExport.dll), ensuring seamless app functionality while executing attacker code in the background. The PoC, tested on v8.8.3 via official installer, shows a message box confirming execution under user privileges upon launching Notepad++. The malicious DLL is notably smaller, highlighting its altered code.

Diagram illustrating Notepad++ DLL hijacking attack: malicious NppExport.dll replacement in plugins folder, proxying to original DLL, code execution flow upon app launch, with icons for Windows search paths, message box PoC, and mitigation shields like moDiagram illustrating Notepad++ DLL hijacking attack: malicious NppExport.dll replacement in plugins folder, proxying to original DLL, code execution flow upon app launch, with icons for Windows search paths, message box PoC, and mitigation shields like mo

No official patch exists yet from Notepad++ developers. Users should verify systems for infections, implement file integrity monitoring on app directories, and download only from official sources. Caution against unexpected app behavior is advised until a fix is released, as the issue stems from fundamental DLL loading practices.
 
 
NPAV offers a robust solution to combat cyber fraud. Protect yourself with our top-tier security product, Z Plus Security