CVE-2026-8435
📛 CVE Title
Concrete CMS 9 before 9.5.0 is vulnerable to Cross Site Request Forgery (CSRF) at concrete/controllers/backend/file approveVersion()
Description
Concrete CMS 9 before 9.5.0 is vulnerable to Cross Site Request Forgery (CSRF) at concrete/controllers/backend/file approveVersion(). 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 21:22 UTC
- Last updated
- 2026-05-22 12:31 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/8xxx/CVE-2026-8435.json
- Linked Threat
- CVE-2026-8435 — CVE-2026-8435
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 22:16:52 UTC
- NVD last modified
- 2026-05-21 22:16:52 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-2026-31363 - Assigner
- ConcreteCMS
- Published
- May 21, 2026, 9:22:30 PM
- Updated
- May 22, 2026, 12:31:23 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-44q4-354f-c826
ENISA description: Concrete CMS 9 before 9.5.0 is vulnerable to Cross Site Request Forgery (CSRF) at concrete/controllers/backend/file approveVersion(). 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-2026-8435 tenable:nvd.nist.gov
- https://www.cve.org/CVERecord?id=CVE-2026-8435 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: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 ...
2026-05-24 12:03 UTC -
web:github.com
Executive Summary: Microsoft is releasing this security advisory to provide information about a vulnerability in .NET 8.0, .NET 9.0, and .NET 10.0. This advisory also provides guidance on what deve...
2026-05-24 12:03 UTC -
web:krebsonsecurity.com
Microsoft expects that exploitation is more likely. May's Patch Tuesday is a welcome respite from April, which saw Microsoft fix a near-record 167 security flaws.
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.bleepingcomputer.com
Today is Microsoft's March 2026 Patch Tuesday with security updates for 79 flaws, including 2 publicly disclosed zero-day vulnerabilities.
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
Microsoft has rolled out its March 2026 Patch Tuesday updates, delivering a fresh batch of security fixes designed to keep Windows environments protected from emerging threats.
2026-05-26 03:00 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 03:00 UTC -
web:msrc.microsoft.com
The Microsoft Security Response Center (MSRC) investigates all reports of security vulnerabilities affecting Microsoft products and services, and provides the information here as part of the ongoing effort to help you manage security risks and help keep your systems protected.
2026-05-26 03:00 UTC -
web:techdocs.broadcom.com
Patch Category Security Patch Severity Critical Host Reboot Required Yes Virtual Machine Migration or Shutdown Required Yes Affected Hardware N/A Affected Software N/A Affected VIBs Included VMware_bootbank_esx-update_8..3-.60.24585383 VMware_bootbank_loadesx_8..3-.60.24585383 PRs Fixed N/A CVE numbers N/A Due to their dependency on the esx ...
2026-05-26 03:00 UTC -
web:www.lansweeper.com
Lansweeper gives you the latest news and reports about Microsoft patch tuesday updates. Detect outdated versions in your IT network and start patching them
2026-05-26 03:00 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-8435.json.
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