CVE-2026-21916

published 2026-04-09

CVE-2026-21916: A UNIX Symbolic Link (Symlink) Following vulnerability in the CLI of Juniper Networks Junos OS allows a local, authenticated attacker with low privileges to…

Priority P3 41 high 7.3 CVSS 3.1

AV L AC L PR L UI R S U C H I H A H

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

12 ranges

Vendor	Product	Version range	Fixed in
juniper	junos	< 23.2	23.2
juniper	junos	—	—
juniper	junos	—	—
juniper	junos	—	—
juniper	junos	—	—
juniper	junos	—	—
juniper	junos_os	—	—
juniper_networks	junos_os	< 23.2R2-S7	23.2R2-S7
juniper_networks	junos_os	>= 23.4 < 23.4R2-S6	23.4R2-S6
juniper_networks	junos_os	>= 24.2 < 24.2R2-S3	24.2R2-S3
juniper_networks	junos_os	>= 24.4 < 24.4R2-S2	24.4R2-S2
juniper_networks	junos_os	>= 25.2 < 25.2R2	25.2R2

CVSS provenance

nvd v3.1 7.3 HIGH CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H

nvd v4.0 7.0 HIGH CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:U/V:X/RE:M/U:X

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