Instituto Nacional de ciberseguridad. Sección Incibe
Instituto Nacional de Ciberseguridad. Sección INCIBE-CERT

CVE-2026-21901

Gravedad CVSS v4.0:
MEDIA
Tipo:
CWE-476 Desreferencia a puntero nulo (NULL)
Fecha de publicación:
09/07/2026
Última modificación:
10/07/2026

Descripción

*** Pendiente de traducción *** A NULL Pointer Dereference vulnerability in the management daemon (mgd) of Juniper Networks Junos OS and Junos OS Evolved allows a local, high-privileged attacker setting or deactivating a specific SSH configuration parameter to create a Denial of Service (DoS).<br /> <br /> A local high-privileged user configuring or deactivating a specific &amp;#39;system services ssh&amp;#39; configuration parameter can exploit a null pointer dereference in one of the functions used by SSH. The function attempts to dereference a null pointer when accessing certain configuration data, resulting in an mgd process crash and restart. Continued execution of these configuration commands will create a sustained Denial of Service (DoS) condition.<br /> <br /> This issue affects:<br /> Junos OS:<br /> <br /> <br /> * from 22.3 before 22.3R3-S5;<br /> * from 22.4 before 22.4R3-S10;<br /> * from 23.2 before 23.2R2-S7;<br /> * from 23.4 before 23.4R2-S8.<br /> <br /> <br /> <br /> <br /> This issue does not affect Junos OS before 22.3R1.<br /> <br /> <br /> <br /> Junos OS Evolved:<br /> * from 22.3R1-EVO before 23.2R2-S7-EVO;<br /> * from 23.4 before 23.4R2-S8-EVO.<br /> <br /> <br /> This issue does not affect Junos OS Evolved before 22.3R1-EVO.