Juniper Session Smart Router LinkFollowing RCE via Unauth API
CVE-2026-103401 Published on October 28, 2026

Session Smart Router and Session Smart Conductor: An attacker can overwrite arbitrary files as root
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.

Vendor Advisory NVD

Vulnerability Analysis

CVE-2026-103401 can be exploited with network access, and requires small amount of user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to be very high.

Exploitation:
NONE
Automatable:
NO
Technical Impact:
TOTAL
Attack Vector:
NETWORK
Attack Complexity:
LOW
Privileges Required:
LOW
User Interaction:
NONE
Scope:
UNCHANGED
Confidentiality Impact:
HIGH
Integrity Impact:
HIGH
Availability Impact:
HIGH

Weakness Type

What is an insecure temporary file Vulnerability?

The software attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

CVE-2026-103401 has been classified to as an insecure temporary file vulnerability or weakness.


Affected Versions

Juniper Networks Session Smart Router: Juniper Networks Session Smart Conductor: