CVE-2026-81923Network attack vector

Protected-page tampering via missing edit authorization

Published Sep 15, 2026 · Updated Sep 15, 2026

Missing authorization in Concrete CMS before 9.5.3 allows remote authenticated users to alter protected pages through the SEO bulk editor. The saveRecord() action validates the target page's CSRF token but omits canEditPageProperties() before saving the meta title, meta description, and URL handle. Access to the bulk SEO tool plus view permission on a page is sufficient to change its presentation and live URL without page-edit permission.

CVSS severity2.1
Low
EPSS probability0.23%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authorization in Concrete CMS before 9.5.3 allows remote authenticated users to alter protected pages through the SEO bulk editor. The saveRecord() action validates the target page's CSRF token but omits canEditPageProperties() before saving the meta title, meta description, and URL handle. Access to the bulk SEO tool plus view permission on a page is sufficient to change its presentation and live URL without page-edit permission.

The record

CVE
CVE-2026-81923
Published
Sep 15, 2026
Updated
Sep 15, 2026
Vendor
Concrete CMS
Product
Concrete CMS
Classifications
T1565.001
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 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=5.0.0 <=9.5.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Concrete CMS · Concrete CMSversion=5.0.0 <=9.5.2

Published CVSS scores

2.1Concrete CMS security teamCVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:N/VI:L/VA:N/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.

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1565.001Stored Data Manipulation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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