CVE-2026-54211
Tobit Laboratories AG TeamDavid's Webbox application’s endpoint “//serverClient_close.html” is vulnerable to a buffer overflow vulnerability in multiple form data parameters. By submitting excessively long values in these parameters, an authenticated attacker can trigger a server crash, resulting in denial of service. Depending on the stack state or if a stack canary can be disclosed through another vulnerability, this buffer overflow could potentially be exploited for remote code execution, leading to full compromise of the server. This issue affects TeamDavid before Rollout 528.
Starting with Rollout 528 (June 30, 2026), the affected functionality is disabled by default and the vulnerabilities are therefore no longer exposed through this functionality.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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: 9.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.64%
- Percentil entre todas las CVEs puntuadas: 49
- Fecha de la puntuación: 6/10/2026
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
T1190Exploit Public-Facing Applicationinitial access75 % - Impacto principal
T1059Command and Scripting Interpreterexecution70 % - Impacto secundario
T1499.004Application or System Exploitationimpact85 %
Vector CVSS con AV:N/PR:N/UI:N indica explotación remota sin privilegios (T1190). Buffer overflow en parámetros autenticados puede lograr RCE (T1059) o DoS (T1499.004, crash del servidor confirmado).
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-787
Referencias
JSON original (NVD)
Mostrar
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"published": "2026-08-07T10:16:58.170",
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"url": "https://labs.infoguard.ch/posts/22-cves-in-david-a-secure-m365-alternative/",
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"lastModified": "2026-09-07T13:20:29.623",
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