CVE-2026-103401: high-severity vulnerability in Juniper Networks Session Smart Router
Session Smart Router and Session Smart Conductor: An attacker can overwrite arbitrary files as root
Published
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.8epss 0.3%
An Improper Link Resolution Before File Access ('Link Following') vulnerability in the unauthenticated web server handlers in Juniper Networks Session Smart Router and Session Smart Conductor allows a local unprivileged user to overwrite arbitrary files as root via unauthenticated API endpoints.
This vulnerability can be exploited on Mist-managed routers and on unmanaged Routers that have not yet been onboarded to a Conductor. Routers already managed by Conductor are not affected.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
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-2026-103406CRITICALSession Smart Conductor: An unauthenticated attacker causes arbitrary command execution during key management.EPSS 0.5%CVE-2026-103390MEDIUMSession Smart Router and Session Smart Conductor: A malformed HTTP URI causes a service crash during HTTP application identificationEPSS 0.4%