CVE-2026-107615 DLL search order hijacking via screenhooks libraries in TightVNC Server
A local attacker can execute arbitrary code with SYSTEM privileges by planting a malicious DLL in a writable directory due to unsafe DLL loading in TightVNC Server.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-107615?
CVE-2026-107615 is a high-severity vulnerability in GlavSoft TightVNC, published on 8 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
An uncontrolled search path element vulnerability in GlavSoft TightVNC Server for Windows before 2.8.88 allows a local authenticated user to execute arbitrary code with SYSTEM privileges. DynamicLibrary::init() (and ThemeLib) load screenhooks32.dll / screenhooks64.dll with LoadLibrary() using a bare file name and no LOAD_LIBRARY_SEARCH_* flags, so the TightVNC service follows the default DLL search order and loads an attacker-planted DLL from a writable directory earlier in that order (for example, an installation directory with permissive ACLs).
Weakness: CWE-427
Which versions are affected by CVE-2026-107615?
How do I fix CVE-2026-107615?
No fix has been published for CVE-2026-107615 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-107615 being exploited?
There is no known exploitation of CVE-2026-107615 in the wild and no public exploit code.
Sources
Also known as GHSA-c7v7-v5cv-43wm.