Unbounded query cache growth from interpolated JSON paths and splice lists in Ecto
Summary
| CVE | CVE-2026-118391 |
|---|---|
| State | PUBLISHED |
| Assigner | EEF |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-11-04 14:17:29 UTC |
| Updated | 2026-11-05 19:17:11 UTC |
| Description | Allocation of Resources Without Limits or Throttling vulnerability in elixir-ecto ecto allows an unauthenticated remote attacker to exhaust memory in the application and in the database server by sending requests with distinct JSON keys or list lengths where the application interpolates them into json_extract_path/2, field[^key] or splice/1. Ecto caches prepared queries per repository in an ETS table with no size limit and no eviction. Interpolated JSON path elements become part of the query expression instead of its parameters, and splice/1 expands into one placeholder per element, so every distinct key or list length creates a new cache entry. With ecto_sql each entry is also a new prepared statement on the database connection that runs it. None of this memory is released until the processes restart. This issue affects ecto: from 3.4.0 before 3.14.3. |
Risk And Classification
Primary CVSS: v4.0 8.9 HIGH from 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS: 0.004940000 probability, percentile 0.425800000 (date 2026-11-05)
Problem Types: CWE-770 | CWE-770 CWE-770 Allocation of Resources Without Limits or Throttling
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | Secondary | 8.9 | HIGH | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/E:X/C... |
| 4.0 | CNA | CVSS | 8.9 | HIGH | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H |
CVSS v4.0 Breakdown
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Elixir-ecto | Ecto | affected 3.4.0 3.14.3 semver | Not specified |
| CNA | Elixir-ecto | Ecto | affected cb2f03964dac324a9771f84f5088e395326e6de8 eef014ad090d27d1a5b69c0e32a50eabd44ab3bb git | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/elixir-ecto/ecto/security/advisories/GHSA-cxjx-vmm2-qr8r | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | github.com | |
| github.com/elixir-ecto/ecto/issues/1031 | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | github.com | |
| osv.dev/vulnerability/EEF-CVE-2026-118391 | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | osv.dev | |
| github.com/elixir-ecto/ecto/commit/cb2f03964dac324a9771f84f5088e395326e6de8 | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | github.com | |
| github.com/elixir-ecto/ecto/commit/eb03f45b999e2bf67ffae92811233eb6e56dba55 | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | github.com | |
| github.com/elixir-ecto/ecto/commit/eef014ad090d27d1a5b69c0e32a50eabd44ab3bb | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | github.com | |
| github.com/elixir-ecto/ecto/commit/d0e97d8a6e274c81c25fbf08087da8d8b9bae0ea | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | github.com | |
| cna.erlef.org/cves/CVE-2026-118391.html | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | cna.erlef.org | |
| ecto.hexdocs.pm/Ecto.Query.API.html | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | ecto.hexdocs.pm | |
| github.com/elixir-ecto/ecto/issues/4470 | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | github.com | |
| ecto.hexdocs.pm/Ecto.Query.API.html | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | ecto.hexdocs.pm | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Eric Meadows-Jönsson (en)
CNA: Eric Meadows-Jönsson (en)
CNA: José Valim (en)
Additional Advisory Data
Solutions
CNA: Upgrade Ecto to 3.14.3 or later. Queries with interpolated JSON path elements or an interpolated splice/1 list are no longer cached, the same as running them with query_cache: false, so distinct keys and list lengths don't add cache entries.
Workarounds
CNA: Pass the path as a query parameter so it is not part of the cache key. With PostgreSQL: fragment("? #> ?", i.meta, type(^path, {:array, :string})). Alternatively, disable the cache for these queries with Repo.all(query, query_cache: false), or restrict keys and list lengths to a known set before building the query.