CVE-2026-21915 PUBLISHED

JSI Virtual Lightweight Collector: Shell escape allows privilege escalation to root

Assigner: juniper
Reserved: 05.01.2026 Published: 09.04.2026 Updated: 10.04.2026

A Permissive List of Allowed Input vulnerability in the CLI of Juniper Networks Support Insights (JSI) Virtual Lightweight Collector (vLWC) allows a local, high privileged attacker to escalate their privileges to root.

The CLI menu accepts input without carefully validating it, which allows for shell command injection. These shell commands are executed with root permissions and can be used to gain complete control of the system.

This issue affects all JSI vLWC versions before 3.0.94.

CVSS Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
CVSS Score: 6.7

Attack Vector	Local	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	High
Privileges Required	High	Integrity Impact	High
User Interaction	None	Availability Impact	High

CVSS 3.1

CVSS Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/R:U/RE:M
CVSS Score: 8.4

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Local	Confidentiality	High	Confidentiality	None
Attack Complexity	Low	Integrity	High	Integrity	None
Attack Requirements	None	Availability	High	Availability	None
Privileges Required	High
User Interaction	None

CVSS 4.0

Product Status

Vendor	Juniper Networks
Product	JSI LWC
Versions	Default: unaffected affected from 0 to 3.0.94 (excl.)

Exploits

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

Workarounds

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

Solutions

The following software releases have been updated to resolve this specific issue: 3.0.94, and all subsequent releases.

References

https://kb.juniper.net/JSA106016

Problem Types

CWE-183 Permissive List of Allowed Input CWE