CVE-2026-100678

Estado: AplazadaAlta (8.3)—

stoatchat before 0.15.5 fails to enforce account-level attempt limits on MFA login challenges, allowing attackers who know a password to guess TOTP codes with only IP-based rate limiting. Attackers can reuse MFA challenge tickets across multiple failed attempts and distribute guesses across IP addresses to bypass rate limiting and gain account access.

CVSS

Versión: 4.0
Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:L/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: 8.3

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.24%
Percentil entre todas las CVEs puntuadas: 14
Fecha de la puntuación: 5/10/2026

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.

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access75 %
Impacto principalT1078.001 Default Accountsstealth · persistence · privilege escalation · initial access80 %
Impacto secundarioT1110.004 Credential Stuffingcredential access75 %

Explotación de aplicación web (stoatchat) accesible remotamente sin autenticación previa (AV:N, PR:N) mediante bypass de controles MFA/TOTP débiles. Permite acceso a cuentas de usuario (T1078.001) por fuerza bruta de códigos MFA (T1110.004) aprovechando límites de intentos insuficientes a nivel de c

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

Password Policies Multi-factor Authentication Vulnerability Scanning User Account Management Privileged Account Management Network Segmentation

Tecnologías afectadas (1)

⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.

Stoatchat — Stoatchat^AI

CWE

CWE-307

Referencias

JSON original (NVD)

Mostrar

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          "options": [
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              "automatable": "no"
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          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
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          "versions": [
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  "published": "2026-09-26T14:16:51.857",
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      "value": "stoatchat before 0.15.5 fails to enforce account-level attempt limits on MFA login challenges, allowing attackers who know a password to guess TOTP codes with only IP-based rate limiting. Attackers can reuse MFA challenge tickets across multiple failed attempts and distribute guesses across IP addresses to bypass rate limiting and gain account access."
    }
  ],
  "lastModified": "2026-09-30T16:17:00.153",
  "sourceIdentifier": "disclosure@vulncheck.com"
}