What’s Vulnerable › Vulnerabilities

CVE-2025-21589: Session Smart Router, Session Smart Conductor, WAN Assurance Router: API Authentication Bypass vulnerability

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-01-27 · updated 2026-06-17
• Weakness: CWE-288

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.

Affected products

• Juniper Networks Session Smart Conductor: from 5.6.7 before 5.6.17; from 6.1 before 6.1.12-lts; from 6.2 before 6.2.8-lts; from 6.3 before 6.3.3-r2 — fixed in 5.6.17, 6.1.12-lts, 6.2.8-lts, 6.3.3-r2
• Juniper Networks Session Smart Router: from 5.6.7 before 5.6.17; from 6.1 before 6.1.12-lts; from 6.2 before 6.2.8-lts; from 6.3 before 6.3.3-r2 — fixed in 5.6.17, 6.1.12-lts, 6.2.8-lts, 6.3.3-r2
• Juniper Networks WAN Assurance Managed Router: from 5.6.7 before 5.6.17; from 6.1 before 6.1.12-lts; from 6.2 before 6.2.8-lts; from 6.3 before 6.3.3-r2 — fixed in 5.6.17, 6.1.12-lts, 6.2.8-lts, 6.3.3-r2

How to fix

Upgrade to a fixed version: Juniper Networks Session Smart Conductor 5.6.17, 6.1.12-lts, 6.2.8-lts, 6.3.3-r2; Juniper Networks Session Smart Router 5.6.17, 6.1.12-lts, 6.2.8-lts, 6.3.3-r2; Juniper Networks WAN Assurance Managed Router 5.6.17, 6.1.12-lts, 6.2.8-lts, 6.3.3-r2. Check the vendor advisory for mitigations.

References

• https://kb.juniper.net/JSA94663
• https://support.juniper.net/support/eol/software/ssr/
• https://supportportal.juniper.net/

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