CVE-2026-77814

/// Technical description

is_path_trusted in scripts/iib/api.py compares the requested path against each allowed parent directory with path.startswith(parent_path), without appending a path separator. A directory whose name merely begins with an allowed path therefore satisfies the comparison, so where /data/images is allowed a request for /data/images_private/secret.txt is treated as trusted and served by FileResponse, disclosing files the confinement was meant to exclude. Whether the check applies depends on get_enable_access_control in scripts/iib/tool.py: it returns true when IIB_ACCESS_CONTROL is set to enable, false when set to disable, and otherwise true when the host Stable Diffusion WebUI was started with share, ngrok, listen or server_name, falling back to false. Confinement is therefore active in the network-exposed WebUI deployments that rely on it, while a standalone run with no such option serves every readable file regardless of this flaw. The fix compares against parent_path joined with os.sep.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References