RCE in Juniper Junos
CVE-2026-33791
An OS Command Injection vulnerability in the CLI processing of Juniper Networks Junos OS and Junos OS Evolved allows a local, high-privileged attacker executing specific, crafted CLI commands to inject arbitrary shell commands as root, leading to a complete compromise of the system. Certain 'set system' commands, when executed with crafted arguments, are not properly sanitized, allowing for arbitrary shell injection. These shell commands are executed as root, potentially allowing for complete control of the vulnerable system. This issue affects: Junos OS: * all versions before 22.4R3-S8, * from 23.2 before 23.2R2-S5, * from 23.4 before 23.4R2-S7, * from 24.2 before 24.2R2-S2, * from 24.4 before 24.4R2, * from 25.2 before 25.2R2; Junos OS Evolved: * all versions before 22.4R3-S8-EVO, * from 23.2 before 23.2R2-S5-EVO, * from 23.4 before 23.4R2-S7-EVO, * from 24.2 before 24.2R2-S2-EVO, * from 24.4 before 24.4R2-EVO, * from 25.2 before 25.2R1-S1-EVO, 25.2R2-EVO.
Vulnerability class: Command Injection (OS Command Injection)
EPSS: 0.007 (49.1th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.7 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Juniper Junos — versions 22.4, 23.2, 23.4
- Juniper Junos_os_evolved — versions 22.4, 23.2, 23.4
- Juniper Networks Junos Os — versions 0, 23.2, 23.4
- Juniper Networks Junos Os Evolved — versions 0, 23.2, 23.4
Weakness classification (CWE)
References
- sirt@juniper.net (vendor-advisory, Mitigation, Vendor Advisory)
- sirt@juniper.net (vendor-advisory)
Frequently asked questions
- What is CVE-2026-33791?
- CVE-2026-33791 is a medium-severity vulnerability in Juniper Junos, classified under OS Command Injection. CVSS score: 6.7/10. Published 2026-04-09.
- How severe is CVE-2026-33791?
- Medium severity. CVSS v3 base score is 6.7 out of 10.