Quick answers
- Is CVE-2026-85664 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-85664 being exploited in the wild.
- How severe is CVE-2026-85664?
- High severity, with a CVSS score of 7.5, published 4 September 2026.
- Which products and versions are affected?
- Chroma 1.5.9.
- Is there a fix for CVE-2026-85664?
- 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-2026-85664 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-85664?
- Check whether you run Chroma 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
The vulnerability is an input validation flaw in Chroma 1.5.9's collection-create API endpoint. The HNSW (Hierarchical Navigable Small World) index parameters max_neighbors, ef_construction, and ef_search lack upper-bound validation, allowing unauthenticated attackers to supply arbitrarily large integer values. When the server attempts index compaction with these oversized parameters, it allocates excessive heap memory, triggering denial of service. The attack requires no authentication and is reachable over the network via the collection-create API. A patch implementing proper parameter bounds validation is required to remediate the issue.
Affected products
- Chroma Chroma 1.5.9
Timeline
- 2026-09-04: disclosed