BISHENG: Code injection in validate API leads to remote code execution
Summary
BISHENG versions 2.3.0, 2.4.0 and 2.4.0-beta1 contain a code injection flaw in the code validation endpoint (validate.py). User-supplied Python code is executed during function definition, so an attacker who can reach the API can run arbitrary commands with the privileges of the BISHENG service. The vendor has not confirmed whether authentication is required, and public proof-of-concept material exists.
Affected
- BISHENG 2.3.0
- BISHENG 2.4.0
- BISHENG 2.4.0-beta1
- Component: src/backend/bisheng/api/v1/validate.py (POST /api/v1/validate/code)
Fixed in
Unknown. No vendor advisory or patch reference has been identified for this CVE.
Workaround
- Restrict access to the /api/v1/validate endpoint to trusted IP ranges or internal networks (third-party guidance, not verified by the vendor).
- Do not expose the instance to the public internet; use a VPN or reverse proxy with IP allowlisting.
- Run the service with a least-privilege account and restrict outbound traffic from the host.
Exploitation
- Not known to be exploited in the wild; not listed in the CISA KEV catalog as far as checked.
- Public proof-of-concept material is described in the vendor's GitHub issue #1995.
- CISA SSVC: exploitation poc, automatable yes, technical impact total.
Our recommendation
- Check whether any BISHENG instance runs 2.3.0, 2.4.0 or 2.4.0-beta1, including Docker images.
- Restrict API access now (IP allowlist or VPN) and confirm the instance is not reachable from the internet.
- Ask the vendor (dataelement, GitHub issue #1995) for a fixed release and upgrade once confirmed; treat the instance as vulnerable until then.
- Review logs for unexpected requests to the validation API and unexpected processes spawned by the service.
- Monitor NVD and the dataelement repository for an advisory.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- GitHub issue dataelement/bisheng #1995 github.com
- CVE-2026-51861 gist (Ro1ME) gist.github.com
- VulDB CVE-2026-51861 vuldb.com
- CVE Brief archive, 6 Oct 2026 cvebrief.com
- Strix CVE-2026-51861 www.strix.ai
- TheHackerWire CVE-2026-51861 www.thehackerwire.com
- BISHENG repository github.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 30 Oct 2026, 21:41.
Original description (NVD)
bisheng 2.3.0, 2.4.0, and 2.4.0-beta1 is vulnerable to Code Injection in src/backend/bisheng/api/v1/validate.py.
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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