[Vulnerability Alert] Critical Security Vulnerability Found in Junos OS Evolved PTX Series (CVE-2026-21902)

• Subject Explanation: [Vulnerability Alert] Critical Security Vulnerability Found in Junos OS Evolved PTX Series (CVE-2026-21902)

• Content Description:
  • Forwarding Taiwan Computer Emergency Response Team / Coordination Center (TWCERT/CC) Security Alert TWCERTCC-200-202602-00000013
  • Juniper Networks released a critical security advisory for its Junos OS Evolved PTX series products (CVE-2026-21902, CVSS: 9.8). This is an incorrect permission assignment for critical resource vulnerability, which allows unauthenticated attackers to execute code as root.
• Impacted Platforms:
  • Junos OS Evolved PTX Series 25.4R1-S1-EVO, 25.4R2-EVO versions
• Suggested Measures:
  • Please update to the following versions: Junos OS Evolved PTX Series 25.4R1-S1-EVO, 25.4R2-EVO, 26.2R1-EVO and later versions
• References:
  1. https://www.twcert.org.tw/tw/cp-169-10736-63e97-1.html

Computer and Communication Center
Network Systems Division