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)

Published · last modified .

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.

EPSS exploit prediction

EPSS: 0.007 (50.2th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 50th percentile — 50.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-33791: held from 0.007 to 0.007.

EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: -0.000

Affected products

Weakness classification (CWE)

References

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.