CVE-2026-8427
📛 CVE Title
Concrete CMS 9 before 9.5.0 is vulnerable to Cross Site Request Forgery (CSRF) at concrete/controllers/backend/file removeFavoriteFolder($id)
Description
Concrete CMS 9 before 9.5.0 is vulnerable to Cross Site Request Forgery (CSRF) at concrete/controllers/backend/file removeFavoriteFolder($id). The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 2.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Yonatan Drori (Tenzai) for reporting.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- ConcreteCMS
- CVSS severity
- LOW
- CVSS score
- 2.3 / 10
- CVSS vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N- Effective score
- 2.3 / 10 LOW source: CNA overview
- CWE(s)
-
CWE-352,CWE-1275 - Reserved
- 2026-05-12
- Published
- 2026-05-21 21:27 UTC
- Last updated
- 2026-05-22 12:33 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/8xxx/CVE-2026-8427.json
- Linked Threat
- CVE-2026-8427 — CVE-2026-8427
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 22:16:51 UTC
- NVD last modified
- 2026-05-21 22:16:51 UTC
- EPSS score
- 0.0002 (probability of exploitation in next 30 days)
- EPSS percentile
- 5.46% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24
NVD / KEV / EPSS data refreshed 2026-05-25 00:24 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-2026-31368 - Assigner
- ConcreteCMS
- Published
- May 21, 2026, 9:27:03 PM
- Updated
- May 22, 2026, 12:33:06 PM
- EUVD base score (CVSS 4.0)
-
2.3 / 10
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - EUVD-reported EPSS
- 0.0200
- Vendors
- Concrete CMS
- Products
-
Concrete CMS (9.0 ≤9.5.0)
- Aliases
-
GHSA-67hj-8239-cmf5
ENISA description: Concrete CMS 9 before 9.5.0 is vulnerable to Cross Site Request Forgery (CSRF) at concrete/controllers/backend/file removeFavoriteFolder($id). The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 2.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Yonatan Drori (Tenzai) for reporting.
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Concrete CMS | Concrete CMS |
9.0 (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-2026-8427 tenable:nvd.nist.gov
- https://www.cve.org/CVERecord?id=CVE-2026-8427 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 (17)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:cisa.gov
Update (08/12/2025): CISA has updated this alert to provide clarification on identifying Exchange Servers on an organization's networks and provided further guidance on running the Microsoft Exchange Health Checker. Update (08/07/2025): CISA issued Emergency Directive (ED) 25-02: Mitigate Microsoft Exchange Vulnerability in response to CVE -2025-53786
2026-05-24 12:03 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 ...
2026-05-24 12:03 UTC -
web:cybersecuritynews.com
Microsoft Exchange Server spoofing flaw, is being actively exploited against on-premises systems before a permanent patch is available.
2026-05-24 12:03 UTC -
web:heimdalsecurity.com
Explore six essential patch management best practices for 2026 to keep your systems secure, up to date, and protected from vulnerabilities.
2026-05-24 12:03 UTC -
web:nvd.nist.gov
An official website of the United States government Here's how you know
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:www.forbes.com
Updated May 17: This article, originally published May 16, has been updated to include further details on the emergency mitigation process recommended after the CVE - 2026 -42897 Microsoft Exchange ...
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.windowslatest.com
Windows 11 April 2026 update adds Narrator Copilot support, faster Settings, File Explorer fixes, and key security improvements.
2026-05-24 12:03 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 12:03 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.
2026-05-26 03:00 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:integsec.com
CVE‑2026‑44277 is a critical‑severity vulnerability in Fortinet's FortiAuthenticator identity‑and‑access‑management platform that allows an unauthenticated attacker to execute arbitrary code or commands on the appliance. This single vulnerability can put your corporate identity store, authentication flows, and downstream business systems into an attacker's hands, making it a ...
2026-05-26 03:00 UTC -
web:nvd.nist.gov
An official website of the United States government Here's how you know
2026-05-26 03:00 UTC -
web:www.bugcrowd.com
Vulnerability mitigation is typically considered a temporary or interim solution. While mitigation measures can reduce the immediate risk associated with vulnerabilities, they may not provide a permanent fix . Organizations should aim to prioritize and plan for complete vulnerability remediation whenever feasible and allocate resources accordingly.
2026-05-26 03:00 UTC -
web:www.microsoft.com
Security Update Guide Notifications Microsoft's free Security Update Guide Notifications provide links to security-related software updates and notification of re-released security updates. These notifications are sent via email throughout the month as needed.
2026-05-26 03:00 UTC -
web:www.secure.com
Learn the difference between vulnerability remediation and mitigation , and how a risk-based strategy can strengthen your security posture.
2026-05-26 03:00 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-8427.json.
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