CVE-2026-85664 (GCVE-0-2026-85664)
Vulnerability from cvelistv5 – Published: 2026-09-04 14:32 – Updated: 2026-09-10 15:08
VLAI
EPSS
VEX
Title
Chroma 1.5.9 Unbounded HNSW Index Parameters Memory Exhaustion
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-10 14:23 UTC
CWE
- CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
References
5 references
| URL | Tags |
|---|---|
| https://github.com/chroma-core/chroma/issues/7225 | issue-tracking |
| https://github.com/chroma-core/chroma | product |
| https://github.com/chroma-core/chroma/blob/1.5.9/… | technical-description |
| https://github.com/chroma-core/chroma/blob/1.5.9/… | technical-description |
| https://www.vulncheck.com/advisories/chroma-1.5.9… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| chroma-core | chroma |
Affected:
0 , ≤ 1.5.9
(semver)
|
guessed |
Date Public
2026-06-09 00:00
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