VulnerabilityDeferred
CVE-2026-85664
Unauthenticated attackers can supply arbitrarily large parameter values to exhaust server memory and cause denial of service during index compaction.
HIGH 8.7EPSS 0.37%
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.37%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 4.0
- 8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.37% probability · 30th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-770
- Source
- disclosure@vulncheck.com
References
- 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
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.