How severe is CVE-2021-47959?

CVE-2021-47959 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-47959 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2021-47959?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2021-47959 have an EU (EUVD) identifier?

Yes. CVE-2021-47959 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34814.

When was CVE-2021-47959 published?

CVE-2021-47959 was published on 2026-05-15 and last updated on 2026-06-17.

CVE-2021-47959

CVE-2021-47959 is a high-severity vulnerability with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-770.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v4: 8.7
EPSS exploit prediction: 0% (36th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-34814
Weakness: CWE-770
Published: 2026-05-15
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2021-47959?: 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.
How severe is CVE-2021-47959?: CVE-2021-47959 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-47959 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2021-47959?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2021-47959 have an EU (EUVD) identifier?: Yes. CVE-2021-47959 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34814.
When was CVE-2021-47959 published?: CVE-2021-47959 was published on 2026-05-15 and last updated on 2026-06-17.

References

Other CWE-770 (Allocation of Resources Without Limits or Throttling) vulnerabilities

CVE-2026-31283 — Critical (CVSS 9.8): In Totara LMS v19.1.5 and before, the forgot password API does not implement rate limiting for the target email…
CVE-2020-37067 — Critical (CVSS 9.8): Filetto 1.0 FTP server contains a denial of service vulnerability in the FEAT command processing that allows attackers…
CVE-2021-47875 — Critical (CVSS 9.8): GeoGebra CAS Calculator 6.0.631.0 contains a denial of service vulnerability that allows attackers to crash the…
CVE-2025-11832 — Critical (CVSS 9.8): Allocation of Resources Without Limits or Throttling vulnerability in Azure Access Technology BLU-IC2, Azure Access…
CVE-2024-44241 — Critical (CVSS 9.8): The issue was addressed with improved bounds checks. This issue is fixed in iOS 18.1 and iPadOS 18.1, macOS Sequoia…
CVE-2022-3439 — Critical (CVSS 9.8): Allocation of Resources Without Limits or Throttling in GitHub repository ikus060/rdiffweb prior to 2.5.0.

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