CVE-2026-57031

Estado: AnalizadaMedia (5.3)—

An Improper Check for Unusual or Exceptional Conditions vulnerability in the packet forwarding engine (PFE) of Juniper Networks Junos OS on MX Series allows adjacent subscribers to bypass configured firewall filters.

On MX Series devices with MPC10/11, LC4800/9600, and MX304 with subscribers configured on static interfaces, ingress firewall filters are not enforced, so that neither protocol level nor upstream bandwidth limitation are in effect.

This issue affects Junos OS on MX with MPC10/11, LC4800/9600/4802, and MX304:

Detalles técnicos trazas, registros y código del informe original

  *  23.2 versions from 23.2R2-S1 before 23.2R2-S7,
  *  23.4 versions from 23.4R2 before 23.4R2-S7,
  *  24.2 versions before 24.2R2-S3,
  *  24.4 versions before 24.4R2-S2,
  *  25.2 versions before 25.2R2.

CVSS

Versión: 4.0
Vector: CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/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:Y/R:X/V:X/RE:M/U:X
Puntuación base: 5.3

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.22%
Percentil entre todas las CVEs puntuadas: 12
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).

Tecnologías afectadas (1)

Juniper — Junos

CWE

CWE-754

Referencias

https://supportportal.juniper.net/JSA110091

JSON original (NVD)

Mostrar

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