CVSS v3
9.8
CRITICAL
EPSS Score
1.6 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
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:
Technical details
- Published
- 2026-01-27
- Last Modified
- 2026-04-15
Frequently asked questions
What is CVE-2025-21589?
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:
Is CVE-2025-21589 actively exploited?
Active exploitation of CVE-2025-21589 has not been confirmed. Its EPSS score was 1.6% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2025-21589?
CVE-2025-21589 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2025-21589 affecting your environment?
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