CVE-2024-21620: Juniper Junos

Medium severity, CVSS 6.1. EPSS: 0.9% chance of exploitation in the next 30 days.

An Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in J-Web of Juniper Networks Junos OS on SRX Series and EX Series allows an attacker to construct a URL that when visited by another user enables the attacker to execute commands with the target's permissions, including an administrator. A specific invocation of the emit_debug_note method in webauth_operation.php will echo back the data it receives. This issue affects Juniper Networks Junos OS on SRX Series and EX Series: * All versions earlier than 20.4R3-S10; * 21.2 versions earlier than 21.2R3-S8; * 21.4 versions earlier than 21.4R3-S6; * 22.1 versions earlier than 22.1R3-S5; * 22.2 versions earlier than 22.2R3-S3; * 22.3 versions earlier than 22.3R3-S2; * 22.4 versions earlier than 22.4R3-S1; * 23.2 versions earlier than 23.2R2; * 23.4 versions earlier than 23.4R2.

Affected products

• Juniper Junos: before 20.4 (fixed in 20.4); version 20.4 only; version 21.2 only; version 21.4 only; version 22.1 only; version 22.2 only; …

Published 2024-01-25. Last modified 2026-06-17.