CVE-2026-51861

bisheng 2.3.0, 2.4.0, and 2.4.0-beta1 is vulnerable to directory traversal in save_download_file (src/backend/bisheng/core/cache/utils.py:290). The vulnerability allows access to files outside the intended area.

BISHENG through 3.0.0-beta4 contains an insecure direct object reference vulnerability that allows authenticated low-privileged users to read other users' parsed documents by supplying arbitrary file_id values. Attackers can enumerate sequential file ids against GET /api/v1/knowledge/file_bbox to retrieve extracted page text from other users' and tenants' knowledge bases.

bisheng 2.3.0, 2.4.0, and 2.4.0-beta1 is vulnerable to Directory Traversal in src/backend/bisheng/linsight/domain/task_exec.py. The vulnerability allows access to files outside the intended directory.

bisheng through 2.6.0-fix2 contains a server-side request forgery vulnerability in the POST /api/v1/workflow/report/callback endpoint that lacks authentication and applies no URL scheme restrictions or host filtering. Unauthenticated attackers can supply arbitrary URLs to enumerate internal network services and cloud metadata endpoints, then retrieve captured responses from object storage using caller-supplied object names.

BISHENG before 2.6.0 contains a remote code execution vulnerability in the workflow run_once endpoint that allows authenticated users to execute arbitrary Python code. Attackers can submit crafted Code node definitions to the POST /api/v1/workflow/run_once endpoint, which executes them with exec() without sandboxing, gaining access to filesystem, credentials, and internal network resources.