CVE-2026-81894 — CVE & Security Advisory Radar

🎯 CVE-2026-81894 🇪🇺 EUVD

📄 .md Alle CVEs anzeigen ✕

CVE-2026-81894 | 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 brows

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.

Klassifikation & Betroffenheit:

Concrete CMS Concrete CMS 5.0.0 ≤9.5.2concretecms concrete_cms *

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') 🎯 High

The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

🛡️ Empfohlene Mitigation: Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid [REF-1482]. Examples of libraries and frameworks that make it easier to generate properly encoded output include Microsoft's Anti-XSS library, the OWASP ESAPI Encoding module, and …

Vollständige Definition bei MITRE ➔

⚔️ Typische Angriffsmuster (CAPEC):

CAPEC-63 · Cross-Site Scripting (XSS) (Very High) CAPEC-85 · AJAX Footprinting (Low) CAPEC-209 · XSS Using MIME Type Mismatch (Medium) CAPEC-588 · DOM-Based XSS (Very High) CAPEC-591 · Reflected XSS (Very High) CAPEC-592 · Stored XSS (Very High)

🧩 Ähnliche Schwachstellen (Hersteller/Klasse/Score-Band):

CVE-2026-8134 9.4 CVE-2026-8135 8.9 CVE-2026-3452 8.9 CVE-2026-18110 8.7 CVE-2026-18111 8.5

🩹 Patch verfügbar (OSV):

🩹 9379c29cb26a1054208b37507b6869811aa75a32 (Commit)

📚 Referenzen & Quellen:

🇪🇺 Original-Eintrag (ENISA EUVD) 🇺🇸 NVD-Eintrag

🔗 documentation.concretecms.org/developers/introduction/version-history/9…

Ausnutzungs-Zeitleiste:

Reserviert 2026

Veröffentlicht 09/2026

Heute 21.09.

CVSS-Vektor-Analyse: 8.5

AV · Angriffsvektor Netzwerk

AC · Komplexität Gering

PR · Privilegien Hoch

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

Veröffentlicht:15.09.2026

Aktualisiert:18.09.2026 18:55

Assigner (CNA):ConcreteCMS

EUVD-ID:EUVD-2026-78833

Quellen: 🇪🇺 EUVD-Datenbank (ENISA) + 🇺🇸 NVD-Anreicherung · 24-h-Cache

CWE-79: Cross-Site Scripting ✓ Offizieller Patch / Advisory verfügbar

💡 Gegenmaßnahme: Sicherheits-Update des Herstellers zeitnah einspielen und Netzwerksegmentierung prüfen.

Tier	2026-09-02	2026-09-20
≥90 %	0	489
≥50 %	0	1477
≥10 %	0	0
<10 %	300	0

Datenquellen & Methodik: Primärquelle ist die EUVD der ENISA (laufender Datenbank-Sync, alle 15 Minuten), abgeglichen mit dem CISA-KEV-Katalog und der NVD — Detail-Dossiers reichern fehlende Felder live per NVD an — mit Fallback auf CIRCL vulnerability-lookup (EU/Non-Profit, aggregiert CVE-, GitHub- und OSV-Advisories). Der CISA-KEV-Katalog (Known Exploited Vulnerabilities, ~1.700 aktiv ausgenutzte Schwachstellen) wird bei jedem Sync vollständig neu geladen und kreuzreferenziert — filterbar über die KEV-Pille. CVSS 3.1 wird nach Ampel-Logik aus Verteidigersicht dekodiert; EPSS bezeichnet die 30-Tage-Exploit-Wahrscheinlichkeit (FIRST.org).

🇪🇺 ENISA EUVD 🇺🇸 NVD ⚠️ CISA KEV ⚡ EPSS

EPSS

0.1%

CVE-2026-81894 🌐 Netzwerk (Remote) 🔐 Admin-Rechte nötig

Concrete CMS

CVE-2026-81894 | 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 brows

CWE-79: Cross-Site Scripting ✓ Offizieller Patch / Advisory verfügbar

💡 Gegenmaßnahme: Sicherheits-Update des Herstellers zeitnah einspielen und Netzwerksegmentierung prüfen.

15.09.2026

🛡️ Details ➔

Zero-Day & Vulnerability Intelligence Hub