BISHENG version 3.0.0‑beta4 and earlier has an IDOR flaw that allows an authenticated low‑privilege user to read other users’ parsed documents by specifying arbitrary file_id values. The breach provides access to extracted page text from documents stored by other tenants, compromising the confidentiality of user data. The weakness is an insecure direct object reference (CWE‑639).

The issue affects any deployment running Bisheng provided by the dataelement vendor up to and including the 3.0.0‑beta4 release. These systems expose the /api/v1/knowledge/file_bbox endpoint, which does not verify file ownership before returning the file bounding box data.

With a CVSS score of 7.1, the vulnerability is considered high severity. Its EPSS score is reported as less than 1 %, indicating a very low but non‑zero probability of exploitation. BISHENG is not listed in CISA’s KEV catalog. Because the flaw requires only authenticated access at a low privilege level, an attacker who can log in to an account can enumerate sequential file identifiers through the vulnerable API, making exploitation straightforward. The impact is limited to data disclosure, but in a multi‑tenant environment it could expose sensitive information from one tenant to another.