GHSA-VPWC-V33Q-MQ89
Vulnerability from github – Published: 2026-04-06 18:00 – Updated: 2026-06-08 19:50Strawberry up until version 0.312.3 is vulnerable to an authentication bypass on WebSocket subscription endpoints. The legacy graphql-ws subprotocol handler does not verify that a connection_init handshake has been completed before processing start (subscription) messages. This allows a remote attacker to skip the on_ws_connect authentication hook entirely by connecting with the graphql-ws subprotocol and sending a start message directly, without ever sending connection_init.
The graphql-transport-ws subprotocol handler is not affected, as it correctly gates subscription operations on a connection_acknowledged flag. However, both subprotocols are enabled by default in all framework integrations that support websockets, and the subprotocol is selected by the client via the Sec-WebSocket-Protocol header.
Any application relying on on_ws_connect for authentication or authorization is affected.
Mitigation: Upgrade to the patched version, or explicitly disable the legacy graphql-ws subprotocol by setting subscription_protocols=[GRAPHQL_TRANSPORT_WS_PROTOCOL] on your GraphQL view/router.
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 0.312.2"
},
"package": {
"ecosystem": "PyPI",
"name": "strawberry-graphql"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.312.3"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-35523"
],
"database_specific": {
"cwe_ids": [
"CWE-306"
],
"github_reviewed": true,
"github_reviewed_at": "2026-04-06T18:00:26Z",
"nvd_published_at": "2026-04-07T17:16:31Z",
"severity": "HIGH"
},
"details": "Strawberry up until version `0.312.3` is vulnerable to an authentication bypass on WebSocket subscription endpoints. The legacy graphql-ws subprotocol handler does not verify that a `connection_init` handshake has been completed before processing start (subscription) messages. This allows a remote attacker to skip the `on_ws_connect` authentication hook entirely by connecting with the graphql-ws subprotocol and sending a start message directly, without ever sending `connection_init`.\n\nThe graphql-transport-ws subprotocol handler is not affected, as it correctly gates subscription operations on a connection_acknowledged flag. However, both subprotocols are enabled by default in all framework integrations that support websockets, and the subprotocol is selected by the client via the Sec-WebSocket-Protocol header.\n\nAny application relying on `on_ws_connect` for authentication or authorization is affected.\n\nMitigation: Upgrade to the patched version, or explicitly disable the legacy graphql-ws subprotocol by setting `subscription_protocols=[GRAPHQL_TRANSPORT_WS_PROTOCOL]` on your GraphQL view/router.",
"id": "GHSA-vpwc-v33q-mq89",
"modified": "2026-06-08T19:50:52Z",
"published": "2026-04-06T18:00:26Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/strawberry-graphql/strawberry/security/advisories/GHSA-vpwc-v33q-mq89"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-35523"
},
{
"type": "WEB",
"url": "https://github.com/strawberry-graphql/strawberry/commit/0977a4e6b41b7cfe3e9d8ba84a43458a2b0c54c2"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/strawberry-graphql/PYSEC-2026-133.yaml"
},
{
"type": "PACKAGE",
"url": "https://github.com/strawberry-graphql/strawberry"
},
{
"type": "WEB",
"url": "https://github.com/strawberry-graphql/strawberry/releases/tag/0.312.3"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
],
"summary": "strawberry-graphql: Authentication bypass via legacy graphql-ws WebSocket subprotocol"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.