CVE-2026-85664

high

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.

References

https://www.vulncheck.com/advisories/chroma-1.5.9-unbounded-hnsw-index-parameters-memory-exhaustion

https://github.com/chroma-core/chroma/issues/7225

https://github.com/chroma-core/chroma/blob/1.5.9/rust/types/src/hnsw_configuration.rs

https://github.com/chroma-core/chroma/blob/1.5.9/rust/frontend/src/auth/mod.rs

https://github.com/chroma-core/chroma

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-71120

Details

Source: Mitre, NVD

Published: 2026-09-04

Updated: 2026-09-10

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C

Severity: High

CVSS v3

Base Score: 7.5

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Severity: High

CVSS v4

Base 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

Severity: High

EPSS

EPSS: 0.00658