Executive brief
Sandboxie-Plus is a security tool used to isolate applications in a 'sandbox' to prevent them from making permanent changes to the underlying Windows system. A vulnerability in its proxy service allows a malicious program running inside the sandbox to break out and gain full SYSTEM administrative privileges on the host computer. This could allow an attacker to bypass security boundaries, steal sensitive data, or take complete control of the machine.
Technical details
The vulnerability exists within the SbieSvc proxy service's GetRawInputDeviceInfoSlave handler in core/svc/GuiServer.cpp. It consists of two flaws that can be chained: an uninitialized stack memory leak and a stack-based buffer overflow. First, by sending an IPC request with cbSize set to 0, the handler returns up to 32KB of uninitialized stack memory, allowing an attacker to leak return addresses and stack cookies to bypass ASLR and /GS protections. Second, the handler performs a memcpy using an attacker-controlled length without bounds checking against the 32KB stack buffer. An attacker can use the leaked information to craft a ROP chain that achieves SYSTEM-level code execution. While Intel CET (Hardware-enforced shadow stacks) can mitigate the ROP execution, it does not prevent the information leak. The issue is fixed in version 1.17.3.
Affected products
- sandboxie-plus Sandboxie-Plus <= 1.17.2
Timeline
- 2026-05-04: advisory: Vendor advisory published on GitHub
- 2026-05-05: disclosed: CVE published to NVD
- 2026-05-05: patched: Fixed in version 1.17.3