GraphQL-core: Denial of service via memory leak in aborted validations
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 2 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-400.
Summary
GraphQL-core, a Python port of the GraphQL.js reference implementation, is affected from 3.3.0a3 before 3.3.1. When a document exceeds max_errors, validate() reuses a module-level ValidationAbortedError, and Python appends frames to its traceback on every raise, so each document, validation context and error set stays in memory for the life of the process. An unauthenticated client can repeatedly submit a small document with more than 100 validation errors, growing memory without bound before query execution until worker memory is exhausted. The flaw does not disclose or modify data; CVSS 3.1 base score 7.5 (HIGH), weaknesses CWE-400 and CWE-401.
Written with Claude Haiku 5.5 from the sources below · 2026-10-31
Description from the CNA
GraphQL-core is a Python port of the GraphQL.js reference implementation. From 3.3.0a3 until 3.3.1, validate() reuses a module-level ValidationAbortedError when a document exceeds max_errors. Python appends frames to the reused exception's traceback on every raise, retaining each document, validation context, and error set for the process lifetime. An unauthenticated client can repeatedly submit a small document with more than 100 validation errors to cause unbounded memory growth before query execution, eventually exhausting worker memory without disclosing or modifying data. This issue is fixed in version 3.3.1.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| graphql-python | graphql-core | 3.3.0a3 to before 3.3.1 | 3.3.1 | Patch available | CNA |
| — | graphql-core (PyPI) | 3.3.0a3 to before 3.3.1 | 3.3.1 | Patch available | GHSA-mpqx-q82w-9x46 |
- graphql-core Vendorgraphql-python Affected 3.3.0a3 to before 3.3.1 Fixed in 3.3.1 Patch available CNA
- graphql-core (PyPI) Vendor— Affected 3.3.0a3 to before 3.3.1 Fixed in 3.3.1 Patch available GHSA-mpqx-q82w-9x46
Remediation
Upgrade graphql-core to version 3.3.1, which fixes the issue. Red Hat rates the issue Important; Red Hat OpenShift AI (RHOAI) and Exploit Intelligence have no fix available yet.
Written with Claude Haiku 5.5 from the sources below · 2026-10-31
- Fix · CNA graphql-core (graphql-python) Fixed in 3.3.1
- Fix · GHSA-mpqx-q82w-9x46 graphql-core (PyPI) Fixed in 3.3.1 Advisory →
Vendor assessments
Red Hat
Red Hat rating: Important. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Exploit Intelligence | Affected | No fix yet |
| Red Hat OpenShift AI (RHOAI) | Affected | No fix yet |
Not affected: 1 product
- Red Hat OpenShift AI (RHOAI)
Timeline
- 2026-10-29 Threatist record created from CVE-2026-119286
- 2026-10-30 Affected versions changed · Red Hat
- 2026-10-30 CVSS score added · Red Hat
- 2026-10-30 CISA SSVC decision points changed
- 2026-10-30 Priority changed: MEDIUM → LOW
- 2026-10-30 Affected versions changed · Red Hat
- 2026-10-30 Alias added: GHSA-mpqx-q82w-9x46
- 2026-10-30 Fix available: PyPI/[email protected] · GHSA-mpqx-q82w-9x46
- 2026-10-30 CVSS score added · GHSA-mpqx-q82w-9x46
- 2026-10-30 Weakness changed · GHSA-mpqx-q82w-9x46
- 2026-10-30 7 new references · GHSA-mpqx-q82w-9x46
References
Other 6
- https://github.com/graphql-python/graphql-core/security/advisories/GHSA-mpqx-q82w-9x46
- https://github.com/graphql-python/graphql-core/issues/287
- https://github.com/graphql-python/graphql-core/pull/288
- https://github.com/graphql-python/graphql-core/commit/3c319fd9f4b8f6c9db4189520561bf8dd0e70be9
- https://github.com/graphql-python/graphql-core/releases/tag/v3.3.1
- https://github.com/graphql-python/graphql-core
More graphql-python vulnerabilities
- TI-2026-79314 Comment tokens bypass max_tokens limit in graphql-core parser CVSS 3.1HIGH 7.5
- TI-2026-79313 Denial of service in GraphQL-core OverlappingFieldsCanBeMerged rule CVSS 3.1HIGH 7.5
Sources
- CVE-2026-119286 · CVE Program
- CVE-2026-119286 · NVD
- FIRST EPSS
- GHSA-mpqx-q82w-9x46 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-119286 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences