CVE-2026-34461

CWE-121Published: May 5, 2026· Updated: May 7, 2026

7.8

CVSS v3.1

EPSS:0.01%probability of exploitation in 30 daysPercentile:3.1th

Official Description

Sandboxie-Plus is an open source sandbox-based isolation software for Windows. In versions 1.17.2 and earlier, the SbieIniServer RunSbieCtrl handler contains a stack buffer overflow. The MSGID_SBIE_INI_RUN_SBIE_CTRL message is handled before normal sandbox and impersonation checks, and for non-sandboxed callers, the handler copies the trailing message payload into a fixed-size WCHAR ctrlCmd[128] stack buffer using memcpy without verifying the length fits within the buffer. The service pipe is created with a NULL DACL, allowing any local interactive process to connect and send an oversized payload to overflow the stack. This can lead to a crash of the SbieSvc service or potential code execution as SYSTEM. This issue has been fixed in version 1.17.3.

NVD Source

Technical Analysis

CVE-2026-34461 requires local access, meaning attackers must already have a foothold on the target system.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 7.8.