CVE-2026-23988
Rufus is a utility that helps format and create bootable USB flash drives. Versions 4.11 and below contain a race condition (TOCTOU) in src/net.c during the creation, validation, and execution of the Fido PowerShell script. Since Rufus runs with elevated privileges (Administrator) but writes the script to the %TEMP% directory (writeable by standard users) without locking the file, a local attacker can replace the legitimate script with a malicious one between the file write operation and the execution step. This allows arbitrary code execution with Administrator privileges. This issue has been fixed in version 4.12_BETA.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 7
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.21%
- Percentil entre todas las CVEs puntuadas: 10
- 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
T1068Exploitation for Privilege Escalationprivilege escalation95 % - Impacto principal
T1059Command and Scripting Interpreterexecution90 % - Impacto secundario
T1548Abuse Elevation Control Mechanismprivilege escalation85 %
Vulnerabilidad TOCTOU local (AV:L, PR:L) en archivo TEMP sin bloqueo. Atacante reemplaza script PowerShell entre escritura y ejecución, logrando ejecución de comandos con privilegios Administrator (escalada de privilegios local).
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)
CWE
- CWE-367
Referencias
JSON original (NVD)
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