MEDIUM CISA KEV

CVE-2025-21590

CVSS v3

4.4

MEDIUM

EPSS Score

0.9%

exploit probability

CISA KEV

Yes

known exploited

Exploitation

SSVC status

Description

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 Known Exploited Vulnerability

Date Added
3/13/2025
Patch Due Date
4/3/2025
Ransomware Use
Unknown

Technical details

Published
3/12/2025

Frequently asked questions

What is CVE-2025-21590?

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.

Is CVE-2025-21590 actively exploited?

Yes. CVE-2025-21590 is on the CISA Known Exploited Vulnerabilities (KEV) catalog, meaning it has been confirmed as actively exploited in the wild. CISA requires federal agencies to patch by 4/3/2025.

What is the CVSS score for CVE-2025-21590?

CVE-2025-21590 has a CVSS v3 base score of 4.4 (MEDIUM severity).

Is CVE-2025-21590 affecting your environment?

Use isMalicious to check if any of your IPs or domains are associated with this vulnerability's IOCs.