CVE-2021-47959Public exploitNetwork attack vector

Unauthenticated service interruption via amplified GraphQL batches

Published May 15, 2026 · Updated May 15, 2026

Resource exhaustion in WPGraphQL 1.3.5 allows remote attackers to interrupt WordPress sites through unauthenticated GraphQL requests. The GraphQL endpoint accepts batched POST bodies containing thousands of duplicated content and comment fields without an effective resource limit, multiplying resolver work until PHP exhausts memory and MySQL connections fail. Public endpoint access is sufficient; the demonstrated consequence is service interruption rather than data disclosure or modification.

CVSS severity8.7
High
EPSS probability0.45%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Resource exhaustion in WPGraphQL 1.3.5 allows remote attackers to interrupt WordPress sites through unauthenticated GraphQL requests. The GraphQL endpoint accepts batched POST bodies containing thousands of duplicated content and comment fields without an effective resource limit, multiplying resolver work until PHP exhausts memory and MySQL connections fail. Public endpoint access is sufficient; the demonstrated consequence is service interruption rather than data disclosure or modification.

The record

CVE
CVE-2021-47959
Published
May 15, 2026
Updated
May 15, 2026
Vendor
WPGraphQL
Product
WPGraphQL
Classifications
CWE-770, T1499.003
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 15, 2026CVE publishedPublication date reported by the CVE source.
  2. May 15, 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=1.3.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

WPGraphQL · WPGraphQLversion=1.3.5

Published CVSS scores

7.5VulnCheckCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
8.7VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

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 exploitPublished

Weakness, pattern, technique

CWE-770Allocation of Resources Without Limits or Throttling
T1499.003Application Exhaustion Flood

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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