# CVE-2026-107727: Strawberry legacy graphql-ws retains naturally completed subscription slots

> Attackers can exhaust subscription slots on persistent WebSocket connections in Strawberry GraphQL, blocking legitimate operations when per-connection limits are configured.

- **Severity:** Low 3.7 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 8 Oct 2026
- **Updated:** 13 Oct 2026
- **Also known as:** GHSA-m952-2w3f-6r8h, PYSEC-2026-4302

## What is CVE-2026-107727?

CVE-2026-107727 is a low-severity denial of service vulnerability in strawberry-graphql strawberry, published on 8 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Strawberry GraphQL is a library for creating GraphQL APIs. From 0.312.3 until 0.327.2, the legacy graphql-ws subscription handler in strawberry/subscriptions/protocols/graphql_ws/handlers.py does not remove naturally completed operations from self.tasks and self.subscriptions. When max_subscriptions_per_connection is configured, a client on a persistent WebSocket connection can use distinct operation IDs for one-shot subscriptions to fill the connection's configured slots even after those subscriptions send complete, causing later legitimate operations on that connection to be rejected with Subscription limit reached. The modern graphql-transport-ws protocol and deployments without the configured per-connection cap are not affected. This issue is fixed in version 0.327.2.

Weakness: CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2026-107727?

3 open source packages ship an affected version, including strawberry-graphql.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `strawberry-graphql` | PyPI | From 0.312.3 | 0.327.2 |
| `strawberry-graphql` | PyPI | From 0.312.3 | 0.327.2 |
| `strawberry-graphql` | PyPI | From 0.312.3 | 0.327.2 |

## How do I fix CVE-2026-107727?

Upgrade strawberry-graphql to 0.327.2 or later.

## Is CVE-2026-107727 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-107727 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-107727 and fix it if it is affected.

What it is: CVE-2026-107727 is a low-severity denial of service vulnerability in strawberry-graphql strawberry, published on 8 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-107727 exists.

Affected packages and fixed versions:
- strawberry-graphql (PyPI): affected from 0.312.3; fixed in 0.327.2
- strawberry-graphql (PyPI): affected from 0.312.3; fixed in 0.327.2
- strawberry-graphql (PyPI): affected from 0.312.3; fixed in 0.327.2

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-107727/ (Markdown: https://insights.sbomify.com/CVE-2026-107727/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-107727
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-107727
- OSV: https://osv.dev/vulnerability/CVE-2026-107727

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-107727/
Summaries are generated and may contain mistakes; the official description above is the record.