# CVE-2026-85664

## Summary

- **CVE ID:** CVE-2026-85664
- **Severity:** HIGH
- **CVSS Score:** 8.7 (CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N)
- **CWE:** CWE-770
- **Published:** Sep 4, 2026
- **Last Modified:** Sep 4, 2026

## Description

Chroma 1.5.9 fails to validate maximum bounds on HNSW index parameters max_neighbors, ef_construction, and ef_search in collection-create requests. Unauthenticated attackers can supply arbitrarily large parameter values to exhaust server memory and cause denial of service during index compaction.

## Affected Products

- chroma-core — chroma (0)

## References

- [CNA](https://github.com/chroma-core/chroma/issues/7225)
- [CNA](https://github.com/chroma-core/chroma)
- [CNA](https://github.com/chroma-core/chroma/blob/1.5.9/rust/types/src/hnsw_configuration.rs)
- [CNA](https://github.com/chroma-core/chroma/blob/1.5.9/rust/frontend/src/auth/mod.rs)
- [CNA](https://www.vulncheck.com/advisories/chroma-1.5.9-unbounded-hnsw-index-parameters-memory-exhaustion)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.37%
- **EPSS Percentile:** 29.7

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-10._