Vulnerability · Published Apr 9, 2026 · Assigned by juniper

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

High 7.3

In plain English

A high-severity security flaw in Junos OS from Juniper Networks. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 3% of all known vulnerabilities).

Severity (CVSS 3.1)7.3High

Exploit odds (30 days)0.1%top 97.3% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

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.

Affected products (as reported)

Vendor	Product	Versions
Juniper Networks	Junos OS	0 – before 23.2R2-S723.4 – before 23.4R2-S624.2 – before 24.2R2-S324.4 – before 24.4R2-S225.2 – before 25.2R2

Weakness: CWE-61 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H

References

https://kb.juniper.net/JSA107807 vendor-advisory