CVE-2026-7886

Source
https://cve.org/CVERecord?id=CVE-2026-7886
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-7886.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-7886
Aliases
Published
2026-05-21T21:18:39.754Z
Modified
2026-07-25T03:56:36.418786260Z
Severity
  • 2.3 (Low) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N CVSS Calculator
Summary
Concrete CMS 9.5.0 and below is vulnerable to IDOR in AddMessage/UpdateMessage via attachments[] parameter
Details

Concrete CMS 9.5.0 and below is vulnerable to IDOR in AddMessage/UpdateMessage via attachments[] parameter which can lead to file permission bypass. The AddMessage and UpdateMessage conversation controllers accept user-supplied file attachment IDs and load files directly via $em->find(File::class, $attachmentID) without checking per-file permissions (canViewFile()). A user who can post in any conversation can reference any file in the CMS file manager by its sequential ID, effectively bypassing the file permission system.  The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 2.3 with a vector CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Tristan Mandani for reporting. if a site truly has private files, the owner should set up a private storage location https://documentation.concretecms.org/user-guide/editors-reference/dashboard/system-and-maintenance/files/file-storage-locations outside of the webroot so that permissions can be checked on view as well. That way, even if a authorized user attaches a file, or otherwise links to it, unauthorized users won't be able to view the file.

Database specific
{
    "cwe_ids": [
        "CWE-639"
    ],
    "cna_assigner": "ConcreteCMS",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/7xxx/CVE-2026-7886.json"
}
References

Affected packages

Git / github.com/concretecms/concretecms

Affected ranges

Type
GIT
Repo
https://github.com/concretecms/concretecms
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
Database specific
{
    "source": [
        "AFFECTED_FIELD",
        "CPE_RANGE"
    ],
    "cpe": "cpe:2.3:a:concretecms:concrete_cms:*:*:*:*:*:*:*:*",
    "extracted_events": [
        {
            "introduced": "5.0"
        },
        {
            "last_affected": "9.5.0"
        },
        {
            "introduced": "0"
        },
        {
            "fixed": "9.5.1"
        }
    ]
}

Affected versions

5.*
5.7.0
5.7.0.1
5.7.0.3
5.7.0.4
5.7.1
5.7.2
5.7.2.1
5.7.3
5.7.3.1
5.7.4.1
5.7.5.2
5.7.5.5
5.7.5.6
5.7.5.7
8.*
8.1.0
8.2.0
8.2.0RC2
8.2.1
8.3.1
8.4.1
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
9.4.0
9.4.0RC1
9.4.0RC2
9.4.1
9.4.2
9.4.3
9.4.4
9.5.0
9.5.0RC1
9.5.0RC2

Database specific

source
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-7886.json"