CVE-2026-35526Network attack vector

Denial of service via unbounded WebSocket subscriptions

Published Apr 7, 2026 · Updated Apr 7, 2026

Denial of service in Strawberry GraphQL before 0.312.3 allows remote attackers to crash API servers through WebSocket subscriptions. The graphql-transport-ws and legacy graphql-ws handlers create an asyncio.Task, Operation object, and async generator for every unique subscribe ID without limiting active subscriptions per connection. A single unauthenticated WebSocket connection can drive linear memory growth and event-loop saturation, degrading the service or causing an out-of-memory crash.

CVSS severity7.5
High
EPSS probability0.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Strawberry GraphQL before 0.312.3 allows remote attackers to crash API servers through WebSocket subscriptions. The graphql-transport-ws and legacy graphql-ws handlers create an asyncio.Task, Operation object, and async generator for every unique subscribe ID without limiting active subscriptions per connection. A single unauthenticated WebSocket connection can drive linear memory growth and event-loop saturation, degrading the service or causing an out-of-memory crash.

The record

CVE
CVE-2026-35526
Published
Apr 7, 2026
Updated
Apr 7, 2026
Vendor
Strawberry GraphQL
Product
Strawberry GraphQL
Classifications
CWE-770, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 7, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 7, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 0.312.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Strawberry GraphQL · Strawberry GraphQLversion=< 0.312.3

Published CVSS scores

7.5GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-770Allocation of Resources Without Limits or Throttling
T1499.004Application or System Exploitation Flood

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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