CVE-2017-20002
Estado: ModificadaAlta (7.8)—
The Debian shadow package before 1:4.5-1 for Shadow incorrectly lists pts/0 and pts/1 as physical terminals in /etc/securetty. This allows local users to login as password-less users even if they are connected by non-physical means such as SSH (hence bypassing PAM's nullok_secure configuration). This notably affects environments such as virtual machines automatically generated with a default blank root password, allowing all local users to escalate privileges.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 7.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.40%
- Percentil entre todas las CVEs puntuadas: 32
- Fecha de la puntuación: 1/10/2026
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 (2)
CWE
- CWE-269
Referencias
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=877374
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=914957
- https://lists.debian.org/debian-lts-announce/2021/03/msg00020.html
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=877374
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=914957
- https://lists.debian.org/debian-lts-announce/2021/03/msg00020.html
JSON original (NVD)
Mostrar
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"vectorString": "AV:L/AC:L/Au:N/C:P/I:P/A:P",
"authentication": "NONE",
"integrityImpact": "PARTIAL",
"accessComplexity": "LOW",
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"affected": [
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"affectedData": [
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"published": "2021-03-17T06:15:12.107",
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"vulnStatus": "Modified",
"weaknesses": [
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"description": [
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"value": "CWE-269"
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"descriptions": [
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"value": "The Debian shadow package before 1:4.5-1 for Shadow incorrectly lists pts/0 and pts/1 as physical terminals in /etc/securetty. This allows local users to login as password-less users even if they are connected by non-physical means such as SSH (hence bypassing PAM's nullok_secure configuration). This notably affects environments such as virtual machines automatically generated with a default blank root password, allowing all local users to escalate privileges."
},
{
"lang": "es",
"value": "El paquete shadow de Debian versiones anteriores a 4.5-1 para Shadow, enumera incorrectamente pts/0 y pts/1 como terminales físicos en /etc/securetty. Esto permite a usuarios locales iniciar sesión como usuarios sin contraseña incluso si están conectados por medios no físicos como SSH (por lo tanto, omitiendo una configuración nullok_secure de PAM). Esto afecta notablemente a entornos como las máquinas virtuales generadas automáticamente con una contraseña root en blanco predeterminada, permitiendo a todos los usuarios locales escalar privilegios"
}
],
"lastModified": "2026-06-17T01:14:54.317",
"configurations": [
{
"nodes": [
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"cpeMatch": [
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