CVE-2026-18120
What it is
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.
At a glance
- Exploitability
- Can be exploited over the network without logging in. Limited direct impact.
- Exploit odds
- 0.4% chance of exploitation in the next 30 days (EPSS).
- Fix
- No patch or advisory is linked yet. Look at mitigations or restrict exposure.
Timeline
- ReservedThe CVE id was reserved by its CNA
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.4% in the next 30 days (EPSS).
- Severity: 6.3 MEDIUM (CVSS).
- Fix: none linked yet, which raises it.
Details
- Published
- Last modified
- Exploit probability
- 0.4% · EPSS, next 30 days
- Weakness
- CWE-862 · Missing authorization
- Record status
- Analyzed
Affected
- Concretecms Concrete Cms < 9.5.4
Attack profile CVSS 4.0 · 6.3
- Attack vector
- Network
- Complexity
- High
- Attack requirements
- Present
- Privileges needed
- None
- User interaction
- None
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
Raw 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-18120.md and follow it. Check whether this project is affected by CVE-2026-18120. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
