CVE-2026-102031: Junos OS Evolved: A low-privileged TACACS+ user causes root command execution when authorization refresh is enabled

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-14 · updated 2026-10-16
Weakness: CWE-78

Description

An OS Command Injection vulnerability in TACACS of Juniper Networks Junos OS Evolved allows a low-privileged TACACS+-authenticated user to execute commands with root privileges when periodic TACACS+ authorization-refresh is enabled.

Affected products

Juniper Networks Junos OS Evolved: before 23.2R2-S7.7-EVO; from 23.4 before 23.4R2-S8.11-EVO; from 24.2 before 24.2R2-S5.6-EVO; from 24.4 before 24.4R2-S5-EVO; from 25.2 before 25.2R2-S2-EVO; from 25.4 before 25.4R1-S3-EVO — fixed in 23.2R2-S7.7-EVO, 23.4R2-S8.11-EVO, 24.2R2-S5.6-EVO, 24.4R2-S5-EVO, 25.2R2-S2-EVO, 25.2X100-D35-EVO

How to fix

Upgrade to a fixed version: Juniper Networks Junos OS Evolved 23.2R2-S7.7-EVO, 23.4R2-S8.11-EVO, 24.2R2-S5.6-EVO, 24.4R2-S5-EVO. Check the vendor advisory for mitigations.

References

https://supportportal.juniper.net/JSA112250

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