#VU103903 Improper authentication in Juniper Networks, Inc. products - CVE-2025-21589

Vulnerability identifier: #VU103903

Vulnerability risk: Critical

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Red]

CVE-ID: CVE-2025-21589

CWE-ID: CWE-287

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Session Smart Router
Server applications / Other server solutions
WAN Assurance Router
Hardware solutions / Routers & switches, VoIP, GSM, etc
Session Smart Conductor
Hardware solutions / Routers & switches, VoIP, GSM, etc

Vendor: Juniper Networks, Inc.

Description

The vulnerability allows a remote attacker to bypass authentication process.

The vulnerability exists due to an unspecified error in the authentication process. A remote non-authenticated attacker can bypass authentication and gain administrative access to the device.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Session Smart Router: before 5.6.17

WAN Assurance Router: before 5.6.17

Session Smart Conductor: before 5.6.17

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External links
https://supportportal.juniper.net/s/article/2025-02-Out-of-Cycle-Security-Bulletin-Session-Smart-Router-Session-Smart-Conductor-WAN-Assurance-Router-API-Authentication-Bypass-Vulnerability-CVE-2025-21589

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.