CVE-2026-21904: Juniper Junos Space

Medium severity, CVSS 6.1. EPSS: 0.2% chance of exploitation in the next 30 days.

An Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Juniper Networks Junos Space allows an attacker to inject script tags in the list filter field that, when visited by another user, enables the attacker to execute commands with the target's permissions, including an administrator. This issue affects all versions of Junos Space before 24.1R5 Patch V3.

Affected products

• Juniper Junos Space: version 1.0 only; version 1.1 only; version 1.2 only; version 1.3 only; version 1.4 only; version 2.0 only; …

Published 2026-04-09. Last modified 2026-07-08.