Sandboxie-Plus versions 1.17.2 and earlier contain two linked defects in the SbieSvc proxy service. When a sandboxed process calls GetRawInputDeviceInfoSlave with a zero-sized request, the handler returns up to 32 KB of uninitialized stack data, exposing return addresses and stack cookies normally protected by ASLR and /GS. A second defect performs an unchecked memcpy into this same 32 KB buffer, allowing a controlled overflow. These weaknesses can be chained: the memory leak supplies the addresses needed to craft a Return‑Oriented Programming chain, which then overruns the stack and runs code with SYSTEM privileges, even from a Security‑Hardened Sandbox. Hardware‑enforced Intel CET shadow stacks block the ROP execution but do not stop the leak. The result is a local privilege escalation that allows a sandboxed user to attain system‑level authority on the host.

The affected product is Sandboxie‑Plus from the sandboxie‑plus vendor. All releases up to and including 1.17.2 are vulnerable when the SbieSvc service is active and the GetRawInputDeviceInfoSlave handler is reachable by sandboxed processes. The exploit requires Windows execution of Sandboxie‑Plus and a sandboxed process capable of sending the IPC request.

The CVSS score of 8.8 classifies this flaw as High severity. No EPSS data is available, and it is not listed in the CISA KEV catalog, so the publicly known exploitation probability is uncertain, but the lack of mitigations on most hosts suggests a realistic threat. The attack is local: an attacker must already have a sandboxed user process and must trigger the vulnerable IPC call. The information‑leak stage bypasses standard mitigations, and the subsequent buffer overflow enables arbitrary code execution through a ROP chain.