CVE-2026-21904

Medium

Description

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.

SeverityMedium

CVSS6.1

Exploit probability—

Product

Juniper Junos Space

PublishedApr 9, 2026

First seenApr 9, 2026

Weakness typeCWE-79Cross-site scripting (XSS)

How to fix

Vendor advisories

kb.juniper.net/JSA106003

Affected products

Product	Affected versions	Fixed in
juniper junos_space	1.0, 1.1, 1.2, 1.3, 1.4, 2.0, 11.1, 11.2, 11.3, 11.4, 12.1, 12.2, 12.3, 13.1, 13.3, 14.1, 15.1, 15.2, 16.1, 16.1r3, 17.1, 17.2, 18.1, 18.1r1, 18.2, 18.3, 18.4, 19.1, 20.3, 21.1, 21.2, 21.3, 22.1, 22.2, 22.3, 23.1, 24.1	—

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