CVE-2026-33791
CWE-78Published: April 9, 2026· Updated: Apr 16, 2026
Official Description
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.
Technical Analysis
CVE-2026-33791 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation requires high privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 6.7.
A proof-of-concept (PoC) exploit exists for CVE-2026-33791. While not yet confirmed in active campaigns, the availability of PoC code increases exploitation risk substantially.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (1)
Quick Facts
Related CVEs (CWE-78)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-33791 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts