CVE-2026-33793: When an unsigned Python op script configuration is present, a local low privileged user can compromise the system

Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.

Affected and fixed versions

Product / branch	Fixed in
Junos OS 0	22.4R3-S7 or later
Junos OS 23.2	23.2R2-S4 or later
Junos OS 23.4	23.4R2-S6 or later
Junos OS 24.2	24.2R1-S2, 24.2R2 or later
Junos OS 24.4	24.4R1-S2, 24.4R2 or later
Junos OS Evolved 0	22.4R3-S7-EVO or later
Junos OS Evolved 23.2	23.2R2-S4-EVO or later
Junos OS Evolved 23.4	23.4R2-S6-EVO or later
Junos OS Evolved 24.2	24.2R2-EVO or later
Junos OS Evolved 24.4	24.4R1-S1-EVO, 24.4R2-EVO or later

Always confirm against the vendor advisory, which lists every fixed hotfix.

What it is

An Execution with Unnecessary Privileges vulnerability in the User Interface (UI) of Juniper Networks Junos OS and Junos OS Evolved allows a local, low-privileged attacker to gain root privileges, thus compromising the system.

When a configuration that allows unsigned Python op scripts is present on the device, a non-root user is able to execute malicious op scripts as a root-equivalent user, leading to privilege escalation.

This issue affects Junos OS:

All versions before 22.4R3-S7,
from 23.2 before 23.2R2-S4,
from 23.4 before 23.4R2-S6,
from 24.2 before 24.2R1-S2, 24.2R2,
from 24.4 before 24.4R1-S2, 24.4R2;

Junos OS Evolved:

All versions before 22.4R3-S7-EVO,
from 23.2 before 23.2R2-S4-EVO,
from 23.4 before 23.4R2-S6-EVO,
from 24.2 before 24.2R2-EVO,
from 24.4 before 24.4R1-S1-EVO, 24.4R2-EVO.

Am I affected?

This issue can affect all systems with Python 3 op scripts enabled:

[ system scripts language python3 ]

However, the risk of malicious exploitation is significantly higher when the ability to execute Python 3 op scripts from a remote location is enabled:

[ system scripts op allow-url-for-python ]

Starting in Junos OS Evolved Release 21.2R1, the junos-defaults configuration group includes 'system scripts language python3' enabled by default.

Workarounds

Use access lists or firewall filters to limit access to the CLI only from trusted hosts and administrators.

Exploitation

Juniper SIRT is not aware of any malicious exploitation of this vulnerability.

KEV status, EPSS score and vendor data refreshed automatically, last on 13 Oct 2026.