CVE-2026-88903Network attack vector

Unauthenticated stored XSS via unsanitized content webhook

Published Oct 11, 2026 · Updated Oct 11, 2026

Stored XSS in Topcontent WordPress Plugin 1.2.1 and earlier allows remote attackers to publish malicious posts via the content webhook. Its request handler improperly authorizes submissions and disables HTML sanitization before storing their content. Exploitation requires an API key that has never been configured; injected JavaScript executes when visitors view the malicious posts.

CVSS severityUnavailable
Unscored
EPSS probability0.28%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in Topcontent WordPress Plugin 1.2.1 and earlier allows remote attackers to publish malicious posts via the content webhook. Its request handler improperly authorizes submissions and disables HTML sanitization before storing their content. Exploitation requires an API key that has never been configured; injected JavaScript executes when visitors view the malicious posts.

The record

CVE
CVE-2026-88903
Published
Oct 11, 2026
Updated
Oct 11, 2026
Vendor
Topcontent
Product
Topcontent WordPress Plugin
Classifications
CWE-79, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 11, 2026CVE publishedPublication date reported by the CVE source.
  2. Oct 11, 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=0 <=1.2.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Topcontent · Topcontent WordPress Pluginversion=0 <=1.2.1

Published CVSS scores

No CVSS assessment is available in this record.

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.

Activity data is delayed. The latest report is Sep 28, 2026.

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

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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

Technologies

Your stack

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