CVE-2026-103409
Session Smart Router: An attacker obtains administrative privileges when an unauthenticated internal endpoint is accessed
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Session Smart Router: An attacker obtains administrative privileges when an unauthenticated internal endpoint is accessed
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.
- Record
CVE-2026-103409- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-306
- Updated
- 2026-11-06
EUVDEUVD-2026-112212
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.
- Record
EUVD-2026-112212- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-06
GitHub AdvisoriesGHSA-4j2g-4264-38mr
A Missing authentication for critical function vulnerability in Juniper Networks Session Smart...
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.
- Record
GHSA-4j2g-4264-38mr- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-306
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-103409- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-306
- Updated
- 2026-11-06
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| exploits, facts | ||
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, PoC in GitHub |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-103409 is a critical vulnerability (CVSS 9.8) in Juniper Networks Session Smart Router, published October 28, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.35%, the 28th percentile. No source names a fixed version.