# CVE-2021-47959: WordPress Plugin WPGraphQL 1.3.5 Denial of Service

> Unauthenticated attackers can cause denial of service in WPGraphQL by sending batched queries with duplicated fields, exhausting server resources.

- **Severity:** High 8.7 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 15 May 2026
- **Updated:** 15 May 2026
- **Also known as:** GHSA-3mgf-xgf9-2wg2

## What is CVE-2021-47959?

CVE-2021-47959 is a high-severity denial of service vulnerability in WPGraphQL, published on 15 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

WordPress Plugin WPGraphQL 1.3.5 contains a denial of service vulnerability that allows unauthenticated attackers to exhaust server resources by sending batched GraphQL queries with duplicated fields. Attackers can send POST requests to the GraphQL endpoint with amplified field duplication payloads to trigger server out-of-memory conditions and MySQL connection errors.

Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling)

## Which versions are affected by CVE-2021-47959?


## How do I fix CVE-2021-47959?

No fix has been published for CVE-2021-47959 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-47959 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-47959 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-47959 and fix it if it is affected.

What it is: CVE-2021-47959 is a high-severity denial of service vulnerability in WPGraphQL, published on 15 May 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-2021-47959 exists.

Affected product: WPGraphQL. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2021-47959/ (Markdown: https://insights.sbomify.com/CVE-2021-47959/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-47959
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-47959
- OSV: https://osv.dev/vulnerability/CVE-2021-47959

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-47959/
Summaries are generated and may contain mistakes; the official description above is the record.