CVE-2025-21589 Session Smart Router, Session Smart Conductor, WAN Assurance Router: API Authentication Bypass vulnerability
A network-based attacker can bypass authentication via an alternate path to gain administrative control of Juniper Session Smart Router devices.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-21589?
CVE-2025-21589 is a critical authentication bypass vulnerability in Juniper Networks Session Smart Conductor, published on 27 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-288
Which versions are affected by CVE-2025-21589?
How do I fix CVE-2025-21589?
No fix has been published for CVE-2025-21589 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2025-21589 being exploited?
There is no known exploitation of CVE-2025-21589 in the wild and no public exploit code.
Sources
Also known as GHSA-vjjg-c428-g9r3.