CVE DATABASE / CVE-2025-21590
CVE-2025-21590
Juniper Junos OS Improper Isolation or Compartmentalization Vulnerability
Confirmed exploited in the wild. Added 2025-03-13.
Federal remediation due 2025-04-03.
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.
Summary
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.
CVSS 3.1 breakdown
| Base score | 4.4 (MEDIUM) |
| Vector | CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N |
| Attack vector | LOCAL |
| Attack complexity | LOW |
| Privileges required | HIGH |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | NONE |
| Integrity | HIGH |
| Availability | NONE |
Weakness type (CWE)
Affected products
Use our free CVE Lookup tool for the latest NVD record, or browse the full CISA KEV catalog.
References
- https://cloud.google.com/blog/topics/threat-intelligence/china-nexus-espionage-targets-juniper-routers
- https://supportportal.juniper.net/JSA93446
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-21590
Data: NIST NVD + CISA KEV. NVD last modified 2025-10-24. Always verify against the vendor advisory before acting.