CVE-2026-21916: A UNIX Symbolic Link (Symlink) Following vulnerability in the CLI of Juniper Networks Junos OS allows a local…

CVE-2026-21916 · Severity: high · CVSS 7.3 · Published 2026-04-09

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.

Technologies: Juniper Junos. Vendors: Juniper.

Quick answers

Is CVE-2026-21916 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-21916 being exploited in the wild.
How severe is CVE-2026-21916?
High severity, with a CVSS score of 7.3, published 9 April 2026.
Which products and versions are affected?
Juniper Junos. The advisory does not name versions.
Is there a fix for CVE-2026-21916?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
Am I affected by CVE-2026-21916?
Check whether you run Juniper Junos. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Affected products

  • Juniper Junos

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