CVE-2021-36888Known exploitationPublic exploitNetwork attack vector

Website compromise via unauthenticated option updates

Published Dec 15, 2021 · Updated Apr 28, 2026

Missing authentication in Image Hover Effects Ultimate 9.6.1 and earlier allows remote attackers to update arbitrary WordPress options. The oxi_settings REST endpoint accepts an unauthenticated rawdata object containing an option name and value, then writes that pair into WordPress configuration. No account or user interaction is required, and changing security-sensitive options enables full website compromise.

CVSS severity9.8
Critical
EPSS probability6.69%
Next 30 days · Sep 16, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authentication in Image Hover Effects Ultimate 9.6.1 and earlier allows remote attackers to update arbitrary WordPress options. The oxi_settings REST endpoint accepts an unauthenticated rawdata object containing an option name and value, then writes that pair into WordPress configuration. No account or user interaction is required, and changing security-sensitive options enables full website compromise.

The record

CVE
CVE-2021-36888
Published
Dec 15, 2021
Updated
Apr 28, 2026
Vendor
Oxilab
Product
Image Hover Effects Ultimate
Classifications
CWE-284, CWE-306
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 15, 2021CVE publishedPublication date reported by the CVE source.
  2. Apr 28, 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=<= 9.6.1 <=9.6.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Oxilab · Image Hover Effects Ultimateversion=<= 9.6.1 <=9.6.1

Published CVSS scores

7.5NVDAV:N/AC:L/Au:N/C:P/I:P/A:P
9.8PatchstackCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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 exploitationReported
Public exploitPublished

Weakness, pattern, technique

CWE-284Improper Access Control
CWE-306Missing Authentication for Critical Function

Public exploit references

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

Reported exploitation

Technologies

Your stack

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Your stack

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