cbcvebase.
CVE-2025-21589
published 2026-01-27

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…

PriorityP271critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
1.43%
69.8th percentile
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

12 ranges
VendorProductVersion rangeFixed in
juniper_networkssession_smart_conductor>= 5.6.7 < 5.6.175.6.17
juniper_networkssession_smart_conductor>= 6.1 < 6.1.12-lts6.1.12-lts
juniper_networkssession_smart_conductor>= 6.2 < 6.2.8-lts6.2.8-lts
juniper_networkssession_smart_conductor>= 6.3 < 6.3.3-r26.3.3-r2
juniper_networkssession_smart_router>= 5.6.7 < 5.6.175.6.17
juniper_networkssession_smart_router>= 6.1 < 6.1.12-lts6.1.12-lts
juniper_networkssession_smart_router>= 6.2 < 6.2.8-lts6.2.8-lts
juniper_networkssession_smart_router>= 6.3 < 6.3.3-r26.3.3-r2
juniper_networkswan_assurance_managed_router>= 5.6.7 < 5.6.175.6.17
juniper_networkswan_assurance_managed_router>= 6.1 < 6.1.12-lts6.1.12-lts
juniper_networkswan_assurance_managed_router>= 6.2 < 6.2.8-lts6.2.8-lts
juniper_networkswan_assurance_managed_router>= 6.3 < 6.3.3-r26.3.3-r2

Detection & IOCsextracted from sources · hover to see the quote

  • Detect network-based authentication bypass attempts targeting Juniper Session Smart Router administrative interface — look for unauthenticated sessions gaining administrative control over the device management plane.
  • ·No evidence of in-the-wild exploitation has been confirmed by Juniper SIRT at time of advisory publication; however, Juniper devices are historically targeted within days of patch release.
  • ·Some WAN Assurance Managed Routers connected to the Mist Cloud have already been automatically patched; verify patch status before assuming all cloud-managed devices are still vulnerable.

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv4.09.3CRITICALCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
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