CVE-2025-21590
medium CISA KEVJuniper Junos OS Improper Isolation or Compartmentalization Vulnerability
Vendor / product: Juniper — Junos OS
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/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N Required action (CISA)
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Affected products
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
References
- https://cloud.google.com/blog/topics/threat-intelligence/china-nexus-espionage-targets-jun... sirt@juniper.net
- https://supportportal.juniper.net/JSA93446 sirt@juniper.net
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-21590 134c704f-9b21-4f2e-91b3-4a467353bcc0