CVE-2025-21589

Critical

Description

An Authentication Bypass Using an Alternate Path or Channel vulnerability in Juniper Networks Session Smart Router may allows a network-based attacker to bypass authentication and take administrative control of the device. This issue affects Session Smart Router:  * from 5.6.7 before 5.6.17,  * from 6.0 before 6.0.8 (affected from 6.0.8), * from 6.1 before 6.1.12-lts,  * from 6.2 before 6.2.8-lts,  * from 6.3 before 6.3.3-r2;  This issue affects Session Smart Conductor:  * from 5.6.7 before 5.6.17,  * from 6.0 before 6.0.8 (affected from 6.0.8), * from 6.1 before 6.1.12-lts,  * from 6.2 before 6.2.8-lts,  * from 6.3 before 6.3.3-r2;  This issue affects WAN Assurance Managed Routers:  * from 5.6.7 before 5.6.17,  * from 6.0 before 6.0.8 (affected from 6.0.8), * from 6.1 before 6.1.12-lts,  * from 6.2 before 6.2.8-lts,  * from 6.3 before 6.3.3-r2.

SeverityCritical
CVSS9.8
Exploit probability—
ProductSession Smart Router
PublishedJan 27, 2026
First seenJan 27, 2026
Weakness typeCWE-288CWE-288

How to fix

Update
  • Juniper Networks Session Smart Router5.6.17, 6.1.12-lts, 6.2.8-lts, 6.3.3-r2 or later
  • Juniper Networks Session Smart Conductor5.6.17, 6.1.12-lts, 6.2.8-lts, 6.3.3-r2 or later
  • Juniper Networks WAN Assurance Managed Router5.6.17, 6.1.12-lts, 6.2.8-lts, 6.3.3-r2 or later

Affected products

ProductAffected versionsFixed in
Juniper Networks Session Smart Router5.6.7 ≤ v < 5.6.17, 6.1 ≤ v < 6.1.12-lts, 6.2 ≤ v < 6.2.8-lts, 6.3 ≤ v < 6.3.3-r25.6.17, 6.1.12-lts, 6.2.8-lts, 6.3.3-r2
Juniper Networks Session Smart Conductor5.6.7 ≤ v < 5.6.17, 6.1 ≤ v < 6.1.12-lts, 6.2 ≤ v < 6.2.8-lts, 6.3 ≤ v < 6.3.3-r25.6.17, 6.1.12-lts, 6.2.8-lts, 6.3.3-r2
Juniper Networks WAN Assurance Managed Router5.6.7 ≤ v < 5.6.17, 6.1 ≤ v < 6.1.12-lts, 6.2 ≤ v < 6.2.8-lts, 6.3 ≤ v < 6.3.3-r25.6.17, 6.1.12-lts, 6.2.8-lts, 6.3.3-r2

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CVE-2025-21589 · Session Smart Router · Dark Radar