CVE-2026-8434
📛 CVE Title
Concrete CMS 9 before 9.5.0 is vulnerable to Cross Site Request Forgery (CSRF) at concrete/controllers/backend/file rescanMultiple()
Description
Concrete CMS 9 before 9.5.0 is vulnerable to Cross Site Request Forgery (CSRF) at concrete/controllers/backend/file rescanMultiple(). 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 21:23 UTC
- Last updated
- 2026-05-22 12:29 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/8xxx/CVE-2026-8434.json
- Linked Threat
- CVE-2026-8434 — CVE-2026-8434
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-2026-31366 - Assigner
- ConcreteCMS
- Published
- May 21, 2026, 9:23:52 PM
- Updated
- May 22, 2026, 12:29:25 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-6qjh-p324-694f
ENISA description: Concrete CMS 9 before 9.5.0 is vulnerable to Cross Site Request Forgery (CSRF) at concrete/controllers/backend/file rescanMultiple(). 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-2026-8434 tenable:nvd.nist.gov
- https://www.cve.org/CVERecord?id=CVE-2026-8434 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 (12)
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 12:03 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 .
2026-05-24 12:03 UTC -
web:cybersecuritynews.com
Microsoft has released its April 2026 Patch Tuesday security update, addressing 168 vulnerabilities across its product portfolio including one actively exploited zero-day and one publicly disclosed flaw that organizations must prioritize immediately.
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: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 12:03 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.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.
2026-05-24 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:nvd.nist.gov
An official website of the United States government Here's how you know
2026-05-26 03:00 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-8434.json.
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