{"id":"CVE-2026-35526","aliases":["GHSA-hv3w-m4g2-5x77","PYSEC-2026-134"],"url":"https://o3.security/vulnerability/CVE-2026-35526","summary":"Strawberry GraphQL affected by a Denial of Service via unbounded WebSocket subscriptions","details":"Strawberry GraphQL is a library for creating GraphQL APIs. Prior to 0.312.3, 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. This vulnerability is fixed in 0.312.3.","published":"2026-04-07T15:23:36.548Z","modified":"2026-08-07T11:31:16.708100602Z","cvss":{"score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"PyPI","name":"strawberry-graphql","fixedVersion":"0.312.3"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/35xxx/CVE-2026-35526.json"},{"type":"ADVISORY","url":"https://github.com/strawberry-graphql/strawberry/security/advisories/GHSA-hv3w-m4g2-5x77"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-35526"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-07T11:31:16.708100602Z"}}