GHSA-hv3w-m4g2-5x77
strawberry-graphql: Denial of Service via unbounded WebSocket subscriptions
Packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| PyPI | strawberry-graphql | < 0.312.3 | 0.312.3 |
Details
As written in the advisory (Markdown source, shown as plain text).
Strawberry GraphQL's WebSocket subscription handlers for both the `graphql-transport-ws` and legacy `graphql-ws` protocols allocate an `asyncio.Task` and associated `Operation` object for every incoming subscribe message without enforcing any limit on the number of active subscriptions per connection.
An unauthenticated attacker can open a single WebSocket connection, send connection_init, and then flood subscribe messages with unique IDs. Each message unconditionally spawns a new `asyncio.Task` and async generator, causing linear memory growth and event loop saturation. This leads to server degradation or an OOM crash.
References
External links from the advisory. They lead to third-party sites.
- https://github.com/strawberry-graphql/strawberry/security/advisories/GHSA-hv3w-m4g2-5x77
- https://nvd.nist.gov/vuln/detail/CVE-2026-35526
- https://github.com/strawberry-graphql/strawberry/commit/0977a4e6b41b7cfe3e9d8ba84a43458a2b0c54c2
- https://github.com/pypa/advisory-database/tree/main/vulns/strawberry-graphql/PYSEC-2026-134.yaml
- https://github.com/strawberry-graphql/strawberry
- https://github.com/strawberry-graphql/strawberry/releases/tag/0.312.3