# CVE-2026-7847: chatchat-space Langchain-Chatchat predictable file identifiers in OpenAI routes

Source: https://junglewise.ai/threats/cve-2026-7847-chatchat-space-langchain-chatchat-predictable-file-identifiers-in  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-05. Updated: 2026-07-24  
License: CC BY 4.0 with a link back

CVE-2026-7847 · Severity: low · CVSS 3.1 · Published 2026-05-05

Langchain-Chatchat is an application framework used to build AI-powered chat systems. A security flaw in how it handles uploaded files allows attackers to guess the unique identifiers for files stored on the server. If successful, an attacker could read, overwrite, or delete sensitive documents and images uploaded by other users, potentially leading to data theft or service disruption.

Technologies: [Chatchat-Space Langchain-Chatchat](https://junglewise.ai/threats/technologies/langchain-chatchat), [langchain-chatchat (PyPI)](https://junglewise.ai/threats/technologies/pypi-langchain-chatchat). Vendors: [Chatchat-Space](https://junglewise.ai/threats/vendors/chatchat-space), [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is CVE-2026-7847 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-7847 being exploited in the wild.

**How severe is CVE-2026-7847?** Low severity, with a CVSS score of 3.1, published 5 May 2026.

**Which products and versions are affected?** Chatchat-Space Langchain-Chatchat 0.3.x up to 0.3.1.3; langchain-chatchat (PyPI) ECOSYSTEM:introduced=0,last_affected=0.3.1.3.

**Is there a fix for CVE-2026-7847?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-7847 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-7847?** Check whether you run Chatchat-Space Langchain-Chatchat or langchain-chatchat (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A vulnerability exists in the `_get_file_id` function within `libs/chatchat-server/chatchat/server/api_server/openai_routes.py`. The application generates file identifiers by base64-encoding a string composed of the file's purpose, upload date, and filename (e.g., `base64("assistants/2026-04-01/photo.png")`). Because this process lacks a random salt or UUID, the identifiers are entirely deterministic. An authenticated attacker can brute-force or guess these identifiers to perform unauthorized file reads, overwrites, or deletions via the `/v1/files/{file_id}` endpoints. While some initial reports suggested local network access was required, the underlying issue is reachable via the network API provided the attacker has valid credentials.

## Affected products

- chatchat-space Langchain-Chatchat 0.3.x up to 0.3.1.3

## Identifiers

- CVE-2026-7847
- GHSA-jv4p-mhmp-69vw
- PYSEC-2026-2557

## Timeline

- 2026-04-13: disclosed: Issue reported to the project maintainers via GitHub issue #5464
- 2026-05-05: advisory: Vulnerability details published via NVD and VulDB

## References

- [https://github.com/3em0/cve_repo/blob/main/Langchain-Chatchat/Vuln-3-Predictable-File-ID.md](https://github.com/3em0/cve_repo/blob/main/Langchain-Chatchat/Vuln-3-Predictable-File-ID.md)
- [https://github.com/chatchat-space/Langchain-Chatchat/](https://github.com/chatchat-space/Langchain-Chatchat/)
- [https://github.com/chatchat-space/Langchain-Chatchat/issues/5464](https://github.com/chatchat-space/Langchain-Chatchat/issues/5464)
- [https://vuldb.com/submit/807796](https://vuldb.com/submit/807796)
- [https://vuldb.com/vuln/361126](https://vuldb.com/vuln/361126)
- [https://vuldb.com/vuln/361126/cti](https://vuldb.com/vuln/361126/cti)

## Related threats

- [Langchain-Chatchat unauthenticated arbitrary command execution via tool invocation](https://junglewise.ai/threats/cve-2026-75128-langchain-chatchat-through-0-3-1-3-exposes-a-post-tools-call-api)
- [Langchain-Chatchat path traversal in knowledge base creation](https://junglewise.ai/threats/cve-2026-51883-the-knowledge-base-creation-and-document-upload-interfaces-in)
- [PYSEC-2026-1512 - Langchain-Chatchat vulnerable to path traversal](https://junglewise.ai/threats/cve-2025-6855-langchain-chatchat-vulnerable-to-path-traversal)
- [PYSEC-2026-1511 - Langchain-Chatchat vulnerable to path traversal](https://junglewise.ai/threats/cve-2025-6854-langchain-chatchat-vulnerable-to-path-traversal)
- [PYSEC-2026-1513 - Langchain-Chatchat has a Path Traversal vulnerability](https://junglewise.ai/threats/cve-2025-6853-langchain-chatchat-has-a-path-traversal-vulnerability)