High severity · published Oct 29, 2026
CVE-2026-119286
GraphQL-core: Denial of service via memory leak in aborted validations
New
7.5
CVSS
–
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
GR
graphql-core · graphql-python
>= 3.3.0a3, < 3.3.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-119286
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-119286
x_refsource_CONFIRM
https://github.com/graphql-python/graphql-core/security/advisories/GHSA-mpqx-q82w-9x46
x_refsource_MISC
https://github.com/graphql-python/graphql-core/issues/287
x_refsource_MISC
https://github.com/graphql-python/graphql-core/pull/288
x_refsource_MISC
https://github.com/graphql-python/graphql-core/commit/3c319fd9f4b8f6c9db4189520561bf8dd0e70be9
x_refsource_MISC
https://github.com/graphql-python/graphql-core/releases/tag/v3.3.1
More from graphql-core
7.5
CVE-2026-75507
GraphQL-core: Denial of service via quadratic complexity in the OverlappingFieldsCanBeMerged validation rule
7.5
CVE-2026-75508
GraphQL-core: Denial of service via comment tokens bypassing the parser's max_tokens limit
