CVE-2026-81927

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Source

https://cve.org/CVERecord?id=CVE-2026-81927

Import Source

https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-81927.json

JSON Data

https://api.osv.dev/v1/vulns/CVE-2026-81927

Published

2026-09-15T20:21:03Z

Modified

2026-09-17T03:47:15Z

Severity

1.8 (Low) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N CVSS Calculator

Summary

Concrete CMS before 9.5.3 is vulnerable to Stored XSS via SVG upload in "Reject" sanitization mode

Details

Concrete CMS before 9.5.3 contained a stored cross-site scripting vulnerability in SVG file handling. When SVG processing was set to the non-default "Reject files containing potentially harmful elements" mode (concrete.file_manager.images.svg_sanitization.action = reject), uploaded SVGs were checked only against a small built-in blocklist covering the script element and on* event-handler attributes; the broader enshrined/svg-sanitize pass still ran, but its result was discarded, so vectors it would have stripped, such as a javascript: URI in an xlink:href, were stored unmodified and executed when the file was opened directly. A user able to upload files could thereby run arbitrary JavaScript in the browser of any user who viewed the file. The default sanitize mode was not affected. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 1.8 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Oriol Ortiz for reporting.

Database specific

{
    "cna_assigner": "ConcreteCMS",
    "cwe_ids": [
        "CWE-79"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/81xxx/CVE-2026-81927.json"
}

References

Affected packages

Git / github.com/concretecms/concretecms

Affected ranges

Type

GIT

Repo

https://github.com/concretecms/concretecms

Events

Introduced

Last Affected

8fe9708072c3815a5df719b592e4b23b43b4ff7a

Database specific

Show details

{
    "extracted_events": [
        {
            "introduced": "5.0.0"
        },
        {
            "last_affected": "9.5.2"
        }
    ],
    "source": "AFFECTED_FIELD"
}

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

9.5.1

9.5.2

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-81927.json"