CVE-2021-31251
Estado: ModificadaCrítica (9.8)—
An authentication bypass in telnet server in BF-430 and BF431 232/422 TCP/IP Converter, BF-450M and SEMAC from CHIYU Technology Inc allows obtaining a privileged connection with the target device by supplying a specially malformed request and an attacker may force the remote telnet server to believe that the user has already authenticated.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 9.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 36%
- Percentil entre todas las CVEs puntuadas: 98
- Fecha de la puntuación: 3/10/2026
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).
Tecnologías afectadas (10)
Chiyu-tech — Bf-430 FirmwareChiyu-tech — Bf-431 FirmwareChiyu-tech — Bf-450m FirmwareChiyu-tech — Semac D1 FirmwareChiyu-tech — Semac D2 FirmwareChiyu-tech — Semac D2 N300 FirmwareChiyu-tech — Semac D4 FirmwareChiyu-tech — Semac S1 Osdp FirmwareChiyu-tech — Semac S2 FirmwareChiyu-tech — Semac S3v3 Firmware
CWE
- CWE-287
Referencias
- https://gitbook.seguranca-informatica.pt/cve-and-exploits/cves/chiyu-iot-devices#cve-2021-31251
- https://seguranca-informatica.pt/dancing-in-the-iot-chiyu-devices-vulnerable-to-remote-attacks/#.YLqK1KhKguU
- https://www.chiyu-tech.com/msg/message-Firmware-update-87.html
- https://gitbook.seguranca-informatica.pt/cve-and-exploits/cves/chiyu-iot-devices#cve-2021-31251
- https://seguranca-informatica.pt/dancing-in-the-iot-chiyu-devices-vulnerable-to-remote-attacks/#.YLqK1KhKguU
- https://www.chiyu-tech.com/msg/message-Firmware-update-87.html
JSON original (NVD)
Mostrar
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