High severity · published Oct 28, 2026
CVE-2026-103401
Session Smart Router and Session Smart Conductor: An attacker can overwrite arbitrary files as root
New
8.8
CVSS
–
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SS
Session Smart Conductor · Juniper Networks
before 7.0.5; 7.1.0 before 7.1.7; 7.2.0 before 7.2.3 · source: vendor
SS
Session Smart Router · Juniper Networks
before 7.0.5; 7.1.0 before 7.1.7; 7.2.0 before 7.2.3 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-103401
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-103401
vendor-advisory
https://supportportal.juniper.net/JSA112183
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