# CVE-2026-45829: Chroma ChromaDB code injection in Python backend server

Source: https://junglewise.ai/threats/cve-2026-45829-chroma-chromadb-code-injection-in-python-backend-server  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-18. Updated: 2026-05-29  
License: CC BY 4.0 with a link back

CVE-2026-45829 · Severity: critical · CVSS 4 · Published 2026-05-18

ChromaDB is an open-source vector database used to power AI applications by managing data for semantic search and machine learning models. A security flaw allows an unauthenticated attacker to execute arbitrary code on the server by submitting a specially crafted request to create a data collection. This could lead to a complete takeover of the database server, unauthorized access to sensitive AI training data, and disruption of services relying on the database.

Technologies: [Chroma](https://junglewise.ai/threats/technologies/chroma), [chromadb (PyPI)](https://junglewise.ai/threats/technologies/chromadb). Vendors: [Chroma](https://junglewise.ai/threats/vendors/chroma), [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is CVE-2026-45829 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-45829 being exploited in the wild.

**How severe is CVE-2026-45829?** Critical severity, with a CVSS score of 4, published 18 May 2026.

**Which products and versions are affected?** Chroma 1.0.0 through 1.5.8; chromadb (PyPI) >= 1.0.0, <= 1.5.9, ECOSYSTEM:introduced=1.0.0,last_affected=1.5.9.

**Is there a fix for CVE-2026-45829?** 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-2026-45829 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-45829?** Check whether you run Chroma or chromadb (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 code injection vulnerability exists in the Python backend of ChromaDB within the collection creation endpoint (/api/v2/tenants/{tenant}/databases/{db}/collections). The vulnerability occurs because the server instantiates user-controlled embedding function configurations before performing authentication or authorization checks. Specifically, the 'SentenceTransformerEmbeddingFunction' does not restrict the model source and allows the 'trust_remote_code' parameter to be passed via 'kwargs'. An attacker can exploit this by sending a request that points to a malicious HuggingFace model repository, leading to Remote Code Execution (RCE) when the server attempts to load the model. This affects the Python-based server implementation but not the Rust-based backend.

## Affected products

- ChromaDB chromadb >= 1.0.0, <= 1.5.9

## Identifiers

- CVE-2026-45829
- GHSA-f4j7-r4q5-qw2c
- PYSEC-2026-311

## Timeline

- 2025-11-28: disclosed: Initial report to vendor via email.
- 2025-12-16: other: Vendor acknowledged receipt of report.
- 2026-05-18: advisory: Public disclosure by HiddenLayer.
- 2026-05-18: other: CVE-2026-45829 assigned.

## References

- [https://github.com/chroma-core/chroma/issues/6717](https://github.com/chroma-core/chroma/issues/6717)
- [https://www.hiddenlayer.com/research/chromatoast-served-pre-auth](https://www.hiddenlayer.com/research/chromatoast-served-pre-auth)

## Related threats

- [Chroma authorization bypass in collection access](https://junglewise.ai/threats/cve-2026-92782-chroma-authorization-bypass-in-collection-access)
- [Chroma input validation flaw in HNSW index parameters](https://junglewise.ai/threats/cve-2026-85664-chroma-input-validation-flaw-in-hnsw-index-parameters)
- [ChromaDB Rust project IDOR in collection lookup](https://junglewise.ai/threats/cve-2026-8828-chromadb-rust-project-idor-in-collection-lookup)
- [ChromaDB code injection in update_collection endpoint](https://junglewise.ai/threats/cve-2026-45833-chromadb-code-injection-in-update-collection-endpoint)
- [ChromaDB cross-tenant access bypass in SimpleRBACAuthorizationProvider](https://junglewise.ai/threats/cve-2026-45831-chromadb-cross-tenant-access-bypass-in)