CVE-2025-21590
Junos OS: An local attacker with shell access can execute arbitrary code
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.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- High
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
6.7
Junos OS: An local attacker with shell access can execute arbitrary code
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.
- Record
CVE-2025-21590- CVSS 4.0
- 6.7 Medium
CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 4.4 Medium
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-653
- Updated
- 2026-11-02
EUVDEUVD-2025-6303
6.7
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.
- Record
EUVD-2025-6303- CVSS 4.0
- 6.7 Medium
CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-jwv5-xmf5-mp56
6.7
An Improper Isolation or Compartmentalization vulnerability in the kernel of Juniper Networks...
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.
- Record
GHSA-jwv5-xmf5-mp56- CVSS 4.0
- 6.7 Medium
CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 4.4 Medium
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-653
- Updated
- 2026-11-02
CISA KEV No score
Juniper Junos OS Improper Isolation or Compartmentalization Vulnerability
Juniper Junos OS contains an improper isolation or compartmentalization vulnerability. This vulnerability could allows a local attacker with high privileges to inject arbitrary code.
- Record
CVE-2025-21590- Weakness
- CWE-653
- Updated
- 2026-11-02
NVD
6.7
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.
- Record
CVE-2025-21590- CVSS 4.0
- 6.7 Medium
CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 4.4 Medium
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-653
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| exploitation | ||
| first indexed | CVE List, EUVD, GitHub Advisories, CISA KEV, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2025-21590 is a medium vulnerability (CVSS 6.7) in Juniper Junos, published March 12, 2025. CISA lists it as known to be exploited, since March 13, 2025. EUVD reports exploitation since March 13, 2025. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.75%, the 77th percentile. No source names a fixed version.