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.

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History

Fri, 04 Sep 2026 16:15:00 +0000

Type Values Removed Values Added
First Time appeared Chroma-core
Chroma-core chroma
Vendors & Products Chroma-core
Chroma-core chroma

Fri, 04 Sep 2026 14:45:00 +0000

Type Values Removed Values Added
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.
Title Chroma 1.5.9 Unbounded HNSW Index Parameters Memory Exhaustion
Weaknesses CWE-770
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

cvssV4_0

{'score': 8.7, 'vector': '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'}


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cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-09-04T14:32:20.917Z

Reserved: 2026-09-04T13:32:28.993Z

Link: CVE-2026-85664

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-09-04T15:17:44.097

Modified: 2026-09-04T15:17:44.097

Link: CVE-2026-85664

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-04T16:00:05Z

Weaknesses