CVE-2021-37598Public exploitNetwork attack vector

Unauthenticated data disclosure via trailing question mark

Published Aug 19, 2021 · Updated Aug 4, 2024

Incorrect authorization in WP Cerber before 8.9.3 allows remote attackers to read WordPress REST API data without authentication. The /wp-json request check fails to recognize the protected REST endpoint when a trailing question mark is appended, so the access-control list is not applied. Any network-reachable installation with REST API access blocked by WP Cerber is exposed, allowing disclosure of users, posts, authors, and IP addresses without data modification.

CVSS severity5.3
Medium
EPSS probability2.35%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Incorrect authorization in WP Cerber before 8.9.3 allows remote attackers to read WordPress REST API data without authentication. The /wp-json request check fails to recognize the protected REST endpoint when a trailing question mark is appended, so the access-control list is not applied. Any network-reachable installation with REST API access blocked by WP Cerber is exposed, allowing disclosure of users, posts, authors, and IP addresses without data modification.

The record

CVE
CVE-2021-37598
Published
Aug 19, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-863, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 19, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
5.0NIST NVDAV:N/AC:L/Au:N/C:P/I:N/A: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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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-863Incorrect Authorization
T1190Exploit Public-Facing Application

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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