CVE-2026-85664

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

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

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-04 15:17

Updated : 2026-09-10 16:18

NVD link : CVE-2026-85664

Mitre link : CVE-2026-85664

CVE.ORG link : CVE-2026-85664

JSON object : View

Products Affected

No product.

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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