CVE-2026-55790
Craft CMS is a content management system (CMS). In versions 5.0.0-RC1 through 5.9.22 and 4.0.0-RC1 through 4.17.15, an attacker with only a GitHub account can plant a JavaScript payload in a craftcms/cms issue title. When a Craft admin uses the CraftSupport widget’s "Give feedback" screen and types a search term that returns the poisoned issue, the payload executes in the admin’s control panel session. No control panel account or elevated privileges are required on the attacker’s side. This issue has been fixed in versions 4.17.16 and 5.9.23.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Puntuación base: 7.4
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.46%
- Percentil entre todas las CVEs puntuadas: 38
- Fecha de la puntuación: 4/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1189Drive-by Compromiseinitial access95 % - Impacto principal
T1059.007JavaScriptexecution90 % - Impacto secundario
T1078.001Default Accountsstealth · persistence · privilege escalation · initial access75 %
XSS almacenado en títulos de issues de GitHub que se ejecuta en sesión de admin de Craft CMS sin necesidad de cuenta de control panel. UI:A y entrega via drive-by confirm T1189. JavaScript ejecutado en navegador=T1059.007. Acceso a sesión autenticada=T1078.001.
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-79
Referencias
JSON original (NVD)
Mostrar
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