CVE-2021-40658Public exploitNetwork attack vector

Stored XSS via unsanitized article body

Published Jun 14, 2022 · Updated Aug 4, 2024

Stored cross-site scripting in Textpattern 4.8.7 allows remote authenticated users to execute script in a viewer's browser via an article body. The Content > Write > Body workflow stores script-bearing HTML and renders it when the published article is viewed, without neutralizing the payload. Administrative-panel access is required to publish the body, and a victim must open the article; the demonstrated payload exposes browser-accessible cookie data.

CVSS severity4.8
Medium
EPSS probability0.58%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored cross-site scripting in Textpattern 4.8.7 allows remote authenticated users to execute script in a viewer's browser via an article body. The Content > Write > Body workflow stores script-bearing HTML and renders it when the published article is viewed, without neutralizing the payload. Administrative-panel access is required to publish the body, and a victim must open the article; the demonstrated payload exposes browser-accessible cookie data.

The record

CVE
CVE-2021-40658
Published
Jun 14, 2022
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79, T1189
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Jun 14, 2022CVE 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 privilegesadmin

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

3.5NIST NVDAV:N/AC:M/Au:S/C:N/I:P/A:N
4.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/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.

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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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1189Drive-by Compromise

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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