CVE-2026-6826
📛 CVE Title
Concrete 9.5.0 and below has file usage disclosure via missing permission check in Usage controller
Description
Concrete CMS 9.5.0 and below is vulnerable to unauthenticated file usage disclosure via missing permission check in the usage controller. Any unauthenticated visitor can request /ccm/system/dialogs/file/usage/{fID} with any file ID and receive a list of every page that references that file, including page IDs, handles, and full URLs. This includes pages that are otherwise restricted by permissions.The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 6.9 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks Eldudareeno for reporting.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- ConcreteCMS
- CVSS severity
- MEDIUM
- CVSS score
- 6.9 / 10
- CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N- Effective score
- 6.9 / 10 MEDIUM source: CNA overview
- CWE(s)
-
CWE-200 - Reserved
- 2026-04-21
- Published
- 2026-05-21 20:55 UTC
- Last updated
- 2026-05-22 12:27 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/6xxx/CVE-2026-6826.json
- Linked Threat
- CVE-2026-6826 — CVE-2026-6826
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 21:16:32 UTC
- NVD last modified
- 2026-05-21 21:16:32 UTC
- EPSS score
- 0.0004 (probability of exploitation in next 30 days)
- EPSS percentile
- 13.41% 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-2026-31344 - Assigner
- ConcreteCMS
- Published
- May 21, 2026, 8:55:21 PM
- Updated
- May 22, 2026, 12:27:12 PM
- EUVD base score (CVSS 4.0)
-
6.9 / 10
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N - EUVD-reported EPSS
- 0.0300
- Vendors
- Concrete CMS
- Products
-
Concrete CMS (5.0 ≤9.5.0)
- Aliases
-
GHSA-4g7q-44qp-cc5c
ENISA description: Concrete CMS 9.5.0 and below is vulnerable to unauthenticated file usage disclosure via missing permission check in the usage controller. Any unauthenticated visitor can request /ccm/system/dialogs/file/usage/{fID} with any file ID and receive a list of every page that references that file, including page IDs, handles, and full URLs. This includes pages that are otherwise restricted by permissions.The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 6.9 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks Eldudareeno for reporting.
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Concrete CMS | Concrete CMS |
5.0 (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-2026-6826 tenable:nvd.nist.gov
- https://www.cve.org/CVERecord?id=CVE-2026-6826 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 (19)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:access.redhat.com
Learn about our open source products, services, and company. You are here
2026-05-24 12:03 UTC -
web:blog.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.
2026-05-24 12:03 UTC -
web:csrc.nist.gov
Enterprise patch management is the process of identifying, prioritizing, acquiring, installing, and verifying the installation of patches, updates, and upgrades throughout an organization. Patching is more important than ever because of the increasing reliance on technology, but there is often a divide between business/mission owners and security/technology management about the value of ...
2026-05-24 12:03 UTC -
web:krebsonsecurity.com
For a clickable, per- patch breakdown, check out the SANS Internet Storm Center Patch Tuesday roundup. Running into problems applying any of these updates?
2026-05-24 12:03 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 12:03 UTC -
web:support.servicenow.com
Overview The advisories below document publicly disclosed Common Vulnerabilities and Exposures ( CVEs ) in the Now Platform by ServiceNow. Because ServiceNow uses various methods to communicate vulnerability information, patches, and other fixes, customers should review family, security patch , and hotfix release notes, which are available at https://docs.servicenow.com, for a complete list of ...
2026-05-24 12:03 UTC -
web:translate.google.com
Google's service, offered free of charge, instantly translates words, phrases, and web pages between English and over 100 other languages.
2026-05-24 12:03 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 12:03 UTC -
web:www.secure.com
Learn the difference between vulnerability remediation and mitigation , and how a risk-based strategy can strengthen your security posture.
2026-05-24 12:03 UTC -
web:www.zafran.io
Mitigation is the control implemented or the action taken to reduce the impact or likelihood of a vulnerability or exposure being exploited before a fix is available or applied. Remediation is the resolution of the vulnerability or exposure which is completed typically through applying patches, updates, or correcting misconfigurations.
2026-05-24 12:03 UTC -
web:carthageelectronics.com
Status: Actively exploited — CISA KEV listed — patch by May 12, 2026 What Happened On April 28, 2026 , CISA added CVE - 2026 -32202 to its Known Exploited Vulnerabilities (KEV) catalog with a federal remediation deadline of May 12, 2026 . This vulnerability is the result of an incomplete patch Microsoft released in February for CVE - 2026 -21510.
2026-05-26 02:59 UTC -
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 ...
2026-05-26 02:59 UTC -
web:cyberpress.org
The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has added two actively exploited Microsoft Defender vulnerabilities to its Known Exploited Vulnerabilities (KEV) catalog, issuing an urgent remediation directive for federal agencies with a due date of June 3, 2026 .
2026-05-26 02:59 UTC -
web:docs.openclaw.ai
Migration checklist Use this checklist when you already know your old BlueBubbles config and want the shortest safe path: Verify imsg directly on the Mac that runs Messages.app (imsg chats, imsg history, imsg send, and imsg rpc --help). Copy behavior keys from channels.bluebubbles to channels.imessage: dmPolicy, allowFrom, groupPolicy, groupAllowFrom, groups, includeAttachments ...
2026-05-26 02:59 UTC -
web:source.android.com
Android partners are encouraged to fix all issues in this bulletin and use the latest security patch level. Devices that use the 2026 -05-01 security patch level must include all issues associated with that security patch level, as well as fixes for all issues reported in previous security bulletins.
2026-05-26 02:59 UTC -
web:techcommunity.microsoft.com
We wanted to tell you how to address the Exchange Server May 2026 vulnerability CVE - 2026 -42897.
2026-05-26 02:59 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 02:59 UTC -
web:www.pcworld.com
This month's Patch Tuesday brings over 80 fixes for various security vulnerabilities. Fortunately, none are actively being exploited in the wild yet.
2026-05-26 02:59 UTC -
web:www.vulncheck.com
In February, VulnCheck introduced our 2025 Routinely Targeted Vulnerabilities list, a compilation of CVEs researched and exploited by a range of threat actors in 2025. Today, we're releasing a list of 2026 vulnerabilities that our analysts have determined qualify for "Routinely Targeted" status based on a combination of threat actor, ransomware, and botnet targeting, along with public ...
2026-05-26 02:59 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-6826.json.
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