CVE-2026-21916 Junos OS: A low privileged user can escalate their privileges so that they can login as root

High 7.0 Published 9 Apr 2026 Updated 13 Apr 2026

A local low-privileged user can escalate to root via a symlink vulnerability in the CLI, leading to full system compromise.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Local or same network only
Victim action needed: A user has to click or open something
Fix: None listed

What is CVE-2026-21916?

CVE-2026-21916 is a high-severity vulnerability in Juniper Junos, published on 9 Apr 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

Official description

A UNIX Symbolic Link (Symlink) Following vulnerability in the CLI of Juniper Networks Junos OS allows a local, authenticated attacker with low privileges to escalate their privileges to root which will lead to a complete compromise of the system.

When after a user has performed a specific 'file link ...' CLI operation, another user commits (unrelated configuration changes), the first user can login as root.

This issue affects Junos OS: * all versions before 23.2R2-S7, * 23.4 versions before 23.4R2-S6, * 24.2 versions before 24.2R2-S3, * 24.4 versions before 24.4R2-S2, * 25.2 versions before 25.2R2.

This issue does not affect versions 25.4R1 or later.

Weakness: CWE-61

Which versions are affected by CVE-2026-21916?

It affects 1 product.

Products include Juniper Junos.

How do I fix CVE-2026-21916?

No fix has been published for CVE-2026-21916 yet. Limit exposure of the affected software until one is available.

Is CVE-2026-21916 being exploited?

There is no known exploitation of CVE-2026-21916 in the wild and no public exploit code.

All Juniper Junos vulnerabilities

Sources

Also known as GHSA-x5g9-73r3-vh5h.