CVE-2026-8337
Concrete CMS is vulnerable to IDOR in surveys
EPSS 0.19%
Description
Concrete CMS 9.5.0 and below is vulnerable to IDOR in surveys. To be vulnerable, a site would have to be configured in such a way that both public and private surveys are present on the site. An unauthenticated attacker can vote in the restricted survey by submitting the restricted optionID through the public survey’s endpoint.
How to fix CVE-2026-8337
To remediate CVE-2026-8337, upgrade the affected package to a fixed version below.
- Packagist/concrete5/concrete5—upgrade to 9.5.1 or later
Is CVE-2026-8337 being exploited?
Low — EPSS is 0.2%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, < 9.5.1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N |