Vulnerability in Juniper Junos
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 ab…
EPSS: 0.017 (74.0th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 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.
Affected products
- Juniper Junos — versions 21.2, 21.4, 22.2
- Juniper Networks Junos Os — versions 0, 21.4, 22.2
Weakness classification (CWE)
CISA KEV (Known Exploited Vulnerabilities)
This CVE is on the CISA KEV catalog, added on . CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.
BOD 22-01 due date: .
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.
Public proof-of-concept exploits
References
- sirt@juniper.net (vendor-advisory, Vendor Advisory)
- sirt@juniper.net (Third Party Advisory, third-party-advisory)
- 134c704f-9b21-4f2e-91b3-4a467353bcc0 (US Government Resource)
Frequently asked questions
- What is CVE-2025-21590?
- CVE-2025-21590 is a medium-severity vulnerability in Juniper Junos, classified under CWE-653. CVSS score: 4.4/10. Published 2025-03-12.
- How severe is CVE-2025-21590?
- Medium severity. CVSS v3 base score is 4.4 out of 10.
- Is CVE-2025-21590 known to be exploited?
- Yes. CVE-2025-21590 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2025-03-13), indicating it is being actively exploited. 4 public proof-of-concept repositories are indexed.