---
cve: "CVE-2026-81894"
severity: "HIGH"
cvss: 8.5
epss: "0.1%"
vendor: "Concrete CMS"
kev: false
exploited: false
published: "2026-09-15 17:17:27"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-21T09:25:04+02:00"
---

# CVE-2026-81894

> 8.5 HIGH

## Beschreibung

Concrete CMS 9.5.2 and below is vulnerable to stored DOM-based Cross-site Scripting (XSS) via the Gallery block's per-image Caption field because the bundled Magnific Popup lightbox script (concrete/js/features/imagery/frontend.js) re-parses the attribute-decoded caption as HTML through jQuery's .append() in titleSrc instead of inserting it as text. A user with permission to edit a page containing a Gallery block can store a caption that executes in the browser of any visitor who opens that image's lightbox. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 8.5 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N. Thanks Yonatan Drori (Tenzai) for reporting.

## CVSS-Vektor

```
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Hoch | good |

## Patch verfügbar (OSV)

- 9379c29cb26a1054208b37507b6869811aa75a32 (Commit)

## Referenzen

- <https://documentation.concretecms.org/developers/introduction/version-history/953-release-notes>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-81894) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_