CVE-2026-103409criticalCWE-306

CVE-2026-103409: critical vulnerability in Juniper Networks Session Smart Router

Session Smart Router: An attacker obtains administrative privileges when an unauthenticated internal endpoint is accessed

Published

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28Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 9.8epss 0.3%
from disclosure to weapon2 days
Published on NVDOct 28
1st PoC+2d
A Missing authentication for critical function vulnerability in Juniper Networks Session Smart Router allows an unauthenticated network-based attacker to obtain administrative privileges by passing crafted URL parameters to an insecure endpoint running as root. Note that this vulnerability can only be exploited prior to the device being onboarded to Mist/Conductor. The issue can no longer be exploited once a device is onboarded to Mist/Conductor.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
Juniper Networks · Session Smart Router
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
Related CVEs — Juniper Networks Session Smart Router

In the same product, most dangerous first.

CVE-2025-21589CRITICALSession Smart Router, Session Smart Conductor, WAN Assurance Router: API Authentication Bypass vulnerabilityEPSS 1.5%CVE-2026-106079HIGHSession Smart Router and Session Smart Conductor: Improper validation of a field causes privilege escalation when updating the YANG configurationEPSS 1.2%CVE-2026-103403HIGHSession Smart Router and Session Smart Conductor: Unvalidated input causes arbitrary file deletion and command execution when deleting audit rulesEPSS 1.2%CVE-2024-2973CRITICALSession Smart Router(SSR): On redundant router deployments API authentication can be bypassedEPSS 1.1%CVE-2026-103390MEDIUMSession Smart Router and Session Smart Conductor: A malformed HTTP URI causes a service crash during HTTP application identificationEPSS 0.4%CVE-2026-103401HIGHSession Smart Router and Session Smart Conductor: An attacker can overwrite arbitrary files as rootEPSS 0.3%