CVE-2026-101956

Critical

Description

An Improper Authentication vulnerability in the J-Web web management component of Juniper Networks Junos OS allows an unauthenticated remote attacker to execute arbitrary Junos commands with root privileges via the exposed J-Web web interface.

SeverityCritical

CVSS9.8

Exploit probability—

ProductJunos OS

PublishedOct 14, 2026

First seenOct 14, 2026

Weakness typeCWE-287Improper authentication

How to fix

Update

Juniper Networks Junos OS25.2R2-S2, 25.4R1-S3, 26.2R1-S2 or later

Vendor advisories

supportportal.juniper.net/JSA112188

Affected products

Product	Affected versions	Fixed in
Juniper Networks Junos OS	25.2 ≤ v < 25.2R2-S2, 25.4 ≤ v < 25.4R1-S3, 26.2 ≤ v < 26.2R1-S2	25.2R2-S2, 25.4R1-S3, 26.2R1-S2

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