Missing Authorization in legacy Express entries search endpoint allows disclosure of Express entry data
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Attack requirements
- Present
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- Low · None · None
- Fix status
- No fix listed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-862.
Summary
Concrete CMS before 9.5.3 exposed a legacy Express entry search endpoint that returned entry result JSON without invoking the canViewExpressEntries() permission check applied by the normal dashboard and CSV Export flow. An unauthenticated visitor who knew or discovered an Express entity identifier could enumerate that entity's entry search results, disclosing attribute values intended to be restricted to privileged users. For Express entities that do not support entry-specific permissions (i.e., supportsEntrySpecificPermissions() returns false), per-entry permission filtering is additionally disabled via EntryList::ignorePermissions(). The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 6.3 with vector CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks Daniel Powell for reporting.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
No affected products listed by the sources yet.
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:concretecms:concrete_cms:*:*:*:*:*:*:*:* | before 9.5.4 | Vulnerable | Concrete CMS |
- cpe:2.3:a:concretecms:concrete_cms:*:*:*:*:*:*:*:* Versions before 9.5.4 Vulnerable ·Concrete CMS
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2026-18120
- 2026-10-03 Alias added: GHSA-3w9f-9wfp-x8gr
References
More Concrete Cms vulnerabilities
- TI-2026-23602 ConcreteCMS v9.4.7 contains a Denial of Service (DoS) vulnerability in the File Manager… CVSS 3.1MEDIUM 6.5
- TI-2023-23992 A Cross Site Scripting (XSS) vulnerability in Concrete CMS from versions 9.2.0 to 9.2.2… CVSS 3.1MEDIUM 5.4
- TI-2023-26495 Concrete CMS before 8.5.13 and 9.x before 9.2.2 allows unauthorized access because… CVSS 3.1CRITICAL 9.8
- TI-2026-14907 Missing authorization in Concrete CMS CVSS 4.0HIGH 8.7
- TI-2022-06200 Cleartext transmission of sensitive information in https://github.com/concrete5/concrete5 CVSS 3.1CRITICAL 9.8
- TI-2021-17294 An issue was discovered in Concrete CMS through 8.5.5. CVSS 3.1CRITICAL 9.8
Sources
- CVE-2026-18120 · CVE Program
- CVE-2026-18120 · NVD
- FIRST EPSS
- GHSA-3w9f-9wfp-x8gr · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences