CVE-2025-21590 MEDIUM

CVE-2025-21590: Junos OS: An local attacker with shell access can execute arbitrary code

Vendor Juniper Networks
Product Junos OS
Weakness CWE-653
KEV Status Known Exploited
Published March 12, 2025
Last update February 26, 2026
View on NVD All CVEs

CVSS base score

4.4/10
Attack vector Local
Attack complexity Low
Privileges required High
User interaction None
Confidentiality None
Integrity High

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N

What the vulnerability does

01Description

An Improper Isolation or Compartmentalization vulnerability in the kernel of Juniper Networks Junos OS allows a local attacker with high privileges to compromise the integrity of the device. A local attacker with access to the shell is able to inject arbitrary code which can compromise an affected device. This issue is not exploitable from the Junos CLI. This issue affects Junos OS:  * All versions before 21.2R3-S9, * 21.4 versions before 21.4R3-S10,  * 22.2 versions before 22.2R3-S6,  * 22.4 versions before 22.4R3-S6,  * 23.2 versions before 23.2R2-S3,  * 23.4 versions before 23.4R2-S4, * 24.2 versions before 24.2R1-S2, 24.2R2.

CISA mandated remediation

02CISA Required Action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Key dates

03Disclosure timeline

March 12, 2025 CVE published
February 26, 2026 Record updated