GHSA-x2fp-hj8c-mmxh

Suggest an improvement
Source
https://github.com/advisories/GHSA-x2fp-hj8c-mmxh
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-x2fp-hj8c-mmxh/GHSA-x2fp-hj8c-mmxh.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-x2fp-hj8c-mmxh
Aliases
Published
2026-05-21T21:30:38Z
Modified
2026-09-10T03:50:48Z
Severity
  • 5.3 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N CVSS Calculator
  • 6.3 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N CVSS Calculator
Summary
Concrete CMS is vulnerable to authorization bypass in the Calendar Event Frontend Dialog
Details

Concrete CMS 9.5.0 and below is vulnerable to authorization Bypass in the Calendar Event Frontend Dialog which can allow cross-calendar data disclosure. A public calendar block can be used as a pivot point to access private calendar data.

Database specific
{
    "cwe_ids":  [
        "CWE-639"
    ],
    "github_reviewed":  true,
    "github_reviewed_at":  "2026-06-24T18:12:55Z",
    "nvd_published_at":  "2026-05-21T21:16:33Z",
    "severity":  "MODERATE"
}
References

Affected packages

Packagist / concrete5/concrete5

Package

Name
concrete5/concrete5
Purl
pkg:composer/concrete5/concrete5

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
9.5.1

Affected versions

8.*
8.0
8.0.1
8.0.2
8.0.3
8.1.0
8.2.0RC2
8.2.0
8.2.1
8.3.0
8.3.1
8.3.2
8.4.0RC3
8.4.0RC4
8.4.0
8.4.1
8.4.2
8.4.3
8.4.4
8.4.5
8.5.0RC1
8.5.0RC2
8.5.0
8.5.1
8.5.2
8.5.3
8.5.4
8.5.5
8.5.6RC1
8.5.6
8.5.7
8.5.8
8.5.9
8.5.10
8.5.11
8.5.12
8.5.13
8.5.14
8.5.15
8.5.16
8.5.17
8.5.18
8.5.19
8.5.20
8.5.21
9.*
9.0.0RC1
9.0.0RC3
9.0.0RC4
9.0.0
9.0.1
9.0.2
9.1.0
9.1.1
9.1.2
9.1.3
9.2.0RC2
9.2.0
9.2.1
9.2.2
9.2.3
9.2.4
9.2.5
9.2.6
9.2.7
9.2.8
9.2.9
9.3.0
9.3.1
9.3.2
9.3.3
9.3.4
9.3.5
9.3.6
9.3.7
9.3.8
9.3.9
9.4.0RC1
9.4.0RC2
9.4.0
9.4.1
9.4.2
9.4.3
9.4.4
9.4.5
9.4.6
9.4.7
9.4.8
9.5.0RC1
9.5.0RC2
9.5.0

Database specific

source
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-x2fp-hj8c-mmxh/GHSA-x2fp-hj8c-mmxh.json"