CVE-2026-8236
📛 CVE Title
Concrete CMS 9.5.0 and below is vulnerable to IDOR combined with a missing authentication gate for endpoint /ccm/system/dialogs/file/usage/{fID}
Description
Concrete CMS 9.5.0 and below is vulnerable to IDOR combined with a missing authentication gate. The endpoint /ccm/system/dialogs/file/usage/{fID} accepts an integer file ID in the URL and returns internal site structure data (page IDs, versions, URL paths) to anyone who sends a GET request. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 6.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks Winston Crooker for reporting.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- ConcreteCMS
- CVSS severity
- MEDIUM
- CVSS score
- 6.3 / 10
- CVSS vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N- Effective score
- 6.3 / 10 MEDIUM source: CNA overview
- CWE(s)
-
CWE-862 - Reserved
- 2026-05-09
- Published
- 2026-05-21 20:59 UTC
- Last updated
- 2026-05-22 12:26 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/8xxx/CVE-2026-8236.json
- Linked Threat
- CVE-2026-8236 — CVE-2026-8236
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-05-21 22:16:49 UTC
- NVD last modified
- 2026-05-21 22:16:49 UTC
- EPSS score
- 0.0005 (probability of exploitation in next 30 days)
- EPSS percentile
- 15.53% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24
NVD / KEV / EPSS data refreshed 2026-05-25 00:25 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-31347 - Assigner
- ConcreteCMS
- Published
- May 21, 2026, 8:59:07 PM
- Updated
- May 22, 2026, 12:26:44 PM
- EUVD base score (CVSS 4.0)
-
6.3 / 10
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N - EUVD-reported EPSS
- 0.0900
- Vendors
- Concrete CMS
- Products
-
Concrete CMS (5 ≤9.5.0)
- Aliases
-
GHSA-58c8-vvqw-cm7m
ENISA description: Concrete CMS 9.5.0 and below is vulnerable to IDOR combined with a missing authentication gate. The endpoint /ccm/system/dialogs/file/usage/{fID} accepts an integer file ID in the URL and returns internal site structure data (page IDs, versions, URL paths) to anyone who sends a GET request. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 6.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks Winston Crooker for reporting.
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Concrete CMS | Concrete CMS |
5 (affected)
|
— |
Vendor references (1)
References embedded in the original CVE record by the assigning CNA.
Web references (4)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
- https://www.first.org/epss/ tenable:www.first.org
- https://documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notes tenable:documentation.concretecms.org
- https://nvd.nist.gov/vuln/detail/CVE-2026-8236 tenable:nvd.nist.gov
- https://www.cve.org/CVERecord?id=CVE-2026-8236 tenable:www.cve.org
NVD-tagged references (1)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notes ff5b8ace-8b95-4078-9743-eac1ca5451de
Remediations (15)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:community.ui.com
Published: May 21, 2026 Updated: May 22, 2026 Version: 1.1 Revision: 1.1 Summary 1 of 5 A malicious actor with access to the network and high privileges could exploit an Improper Input Validation vulnerability found in UniFi OS devices to execute a Command Injection. Affected Products: UniFi OS Server (Version 5.0.6 and earlier) Mitigation : Update your UniFi OS Server to Version 5.0.8 or later ...
2026-05-24 12:02 UTC -
web:nvd.nist.gov
CVE - 2026 -23262 - In the Linux kernel, the following vulnerability has been resolved: gve: Fix stats report corruption on queue count change The driver and the NIC share a region in memory for stats reporting.
2026-05-24 12:02 UTC -
web:portal.msrc.microsoft.com
The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.
2026-05-24 12:02 UTC -
web:www.cisecurity.org
<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...
2026-05-24 12:02 UTC -
web:www.crowdstrike.com
Microsoft's April 2026 Patch Tuesday addresses 164 CVEs , featuring 8 Critical vulnerabilities, one exploited zero-day, and one disclosed zero-day.
2026-05-24 12:02 UTC -
web:www.helpnetsecurity.com
Microsoft has marked May 2026 Patch Tuesday by releasing fixes for 120+ CVE -numbered vulnerabilities, none of which are actively exploited.
2026-05-24 12:02 UTC -
web:www.oracle.com
This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.
2026-05-24 12:02 UTC -
web:www.penligent.ai
Second, chipset and OEM dependencies make remediation slower and messier than software-only patching. Google's bulletin explains the two Android patch levels for March 2026 and clarifies that devices with security patch levels of 2026 -03-01 or 2026 -03-05 are protected against the associated issues, depending on applicable components.
2026-05-24 12:02 UTC -
web:www.windowslatest.com
Windows 11 April 2026 update adds Narrator Copilot support, faster Settings, File Explorer fixes, and key security improvements.
2026-05-24 12:02 UTC -
web:zecurit.com
Get the complete breakdown of Microsoft's May 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .
2026-05-24 12:02 UTC -
web:cybersecuritynews.com
Microsoft released its March 2026 Patch Tuesday security update on March 10, 2026 , addressing 78 vulnerabilities across Windows, Microsoft Office, Azure, SQL Server, and .NET. The update includes one actively exploited zero-day vulnerability and multiple Critical-rated flaws demanding immediate attention from security teams. The most urgent fix this month is CVE - 2026 -21262, the sole zero-day ...
2026-05-26 03:00 UTC -
web:support.esri.com
The C version of this patch also includes additional bug fixes not related to security, refer to the updated Issues Addressed with this Patch section for the latest details. Important Note - April 20, 2026 : The 11.4 version of the Portal for ArcGIS Security 2026 Update 1 Patch is now available.
2026-05-26 03:00 UTC -
web:threatprotect.qualys.com
With Qualys Policy Audit's out-of-the-box mitigation or Compensatory Controls, which reduce the risk of a vulnerability being exploited because the remediation ( fix / patch ) cannot be done immediately, these security controls are not recommended by any industry standards, such as CIS and DISA-STIG.
2026-05-26 03:00 UTC -
web:windowsreport.com
Microsoft has released its May 2026 Patch Tuesday updates for Windows 11 and Windows 10, shipping as KB5089549 and KB5087544. The updates include fixes for more than 130 security vulnerabilities across Windows, Office, SharePoint, DNS components, and core system services, as Bleeping Computer writes. While no publicly disclosed zero-day vulnerabilities were reported this month, the […]
2026-05-26 03:00 UTC -
web:www.crowdstrike.com
Microsoft has released security updates for 130 vulnerabilities, including 30 critical, in its May 2026 Patch Tuesday rollout.
2026-05-26 03:00 UTC
AI Forensic Analysis
Only Available for Registered Users. Sign in to view.
Raw JSON
The full cvelistV5 record. Download as CVE-2026-8236.json.
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-8236",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "yes"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-05-22T12:26:32.476147Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-05-22T12:26:44.034Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"collectionURL": "https://github.com/concretecms/concretecms",
"defaultStatus": "unaffected",
"product": "Concrete CMS",
"repo": "https://github.com/concretecms/concretecms",
"vendor": "Concrete CMS",
"versions": [
{
"lessThanOrEqual": "9.5.0",
"status": "affected",
"version": "5",
"versionType": "git"
}
]
}
],
"credits": [
{
"lang": "en",
"type": "finder",
"value": "Winston Crooker"
}
],
"descriptions": [
{
"lang": "en",
"supportingMedia": [
{
"base64": false,
"type": "text/html",
"value": "Concrete CMS 9.5.0 and below is vulnerable to IDOR combined with a missing authentication gate. The endpoint <code>/ccm/system/dialogs/file/usage/{fID}</code> accepts an integer file ID in the URL and returns internal site structure data (page IDs, versions, URL paths) to anyone who sends a GET request. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 6.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks Winston Crooker for reporting. "
}
],
"value": "Concrete CMS 9.5.0 and below is vulnerable to IDOR combined with a missing authentication gate. The endpoint\u00a0/ccm/system/dialogs/file/usage/{fID}\u00a0accepts an integer file ID in the URL and returns internal site structure data (page IDs, versions, URL paths) to anyone who sends a GET request. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of\u00a06.3 with vector\u00a0CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks\u00a0Winston Crooker for reporting."
}
],
"impacts": [
{
"capecId": "CAPEC-116",
"descriptions": [
{
"lang": "en",
"value": "CAPEC-116 Excavation"
}
]
}
],
"metrics": [
{
"cvssV4_0": {
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"attackComplexity": "LOW",
"attackRequirements": "PRESENT",
"attackVector": "NETWORK",
"baseScore": 6.3,
"baseSeverity": "MEDIUM",
"exploitMaturity": "NOT_DEFINED",
"privilegesRequired": "NONE",
"providerUrgency": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"userInteraction": "NONE",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N",
"version": "4.0",
"vulnAvailabilityImpact": "NONE",
"vulnConfidentialityImpact": "LOW",
"vulnIntegrityImpact": "NONE",
"vulnerabilityResponseEffort": "NOT_DEFINED"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-862",
"description": "CWE-862",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-05-21T20:59:07.334Z",
"orgId": "ff5b8ace-8b95-4078-9743-eac1ca5451de",
"shortName": "ConcreteCMS"
},
"references": [
{
"tags": [
"release-notes"
],
"url": "https://documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notes"
}
],
"source": {
"advisory": "https://hackerone.com/reports/3681128",
"defect": [
"HackerOne"
],
"discovery": "UNKNOWN"
},
"title": "Concrete CMS 9.5.0 and below is vulnerable to IDOR combined with a missing authentication gate for endpoint /ccm/system/dialogs/file/usage/{fID}",
"x_generator": {
"engine": "Vulnogram 1.0.2"
}
}
},
"cveMetadata": {
"assignerOrgId": "ff5b8ace-8b95-4078-9743-eac1ca5451de",
"assignerShortName": "ConcreteCMS",
"cveId": "CVE-2026-8236",
"datePublished": "2026-05-21T20:59:07.334Z",
"dateReserved": "2026-05-09T15:01:30.954Z",
"dateUpdated": "2026-05-22T12:26:44.034Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}