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

> CVE-2025-21590: Junos OS: An local attacker with shell access can execute arbitrary code. CVSS 4.4 (CVSS 3.1), in CISA KEV.

Canonical: https://rewindex.com/cve/CVE-2025-21590
Last updated: 2026-10-01T18:23:34Z

- Published: 2025-03-12 13:59 UTC · Updated: 2026-10-01 18:23 UTC · Assigner: juniper
- CVSS: 4.4 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N
- EPSS: 1.7%, 77th percentile (scored 2026-10-25)
- CISA KEV: yes, added 2025-03-13, federal due date 2025-04-03, ransomware use: Unknown
- CWE: CWE-653

## 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 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.

## Affected vendors and products

- Juniper Networks: Junos OS

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2025-21590)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2025-21590)
- [https://cloud.google.com/blog/topics/threat-intelligence/china-nexus-espionage-targets-juniper-routers](https://cloud.google.com/blog/topics/threat-intelligence/china-nexus-espionage-targets-juniper-routers)
- [https://supportportal.juniper.net/JSA93446](https://supportportal.juniper.net/JSA93446)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2025-21590 · Markdown: https://rewindex.com/cve/CVE-2025-21590.md · JSON: https://rewindex.com/api/v1/cves/CVE-2025-21590 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T04:04:39.461Z