CVE-2026-102049: Junos OS and Junos OS Evolved: An attacker causes l2cpd crash or root code execution when Unified Access Policy is enabled

Published Oct 14, 2026

Updated

A Stack-based Buffer Overflow vulnerability in the l2cpd process of Juniper Networks Junos OS and Junos OS Evolved allows an adjacent unauthenticated attacker to cause a denial of service or execute arbitrary code with root privileges via LLDP traffic received on an interface with Unified Access Policy enabled.

Affected Software

2 affected components

Juniper Networks Junos OS

Juniper Networks Junos OS Evolved

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade Juniper Junos OS Evolved to a version that resolves this vulnerability.
Fixed in 23.2R2-S7.7-EVO
Upgrade
Upgrade Juniper Junos OS Evolved to a version that resolves this vulnerability.
Fixed in 23.4R2-S8.11-EVO
Upgrade
Upgrade Juniper Junos OS Evolved to a version that resolves this vulnerability.
Fixed in 24.2R2-S5.6-EVO
Upgrade
Upgrade Juniper Junos OS Evolved to a version that resolves this vulnerability.
Fixed in 24.4R2-S5-EVO
Upgrade
Upgrade Juniper Junos OS Evolved to a version that resolves this vulnerability.
Fixed in 25.2R2-S2-EVO
Upgrade
Upgrade Juniper Junos OS Evolved to a version that resolves this vulnerability.
Fixed in 25.2X100-D35-EVO
Upgrade
Upgrade Juniper Junos OS Evolved to a version that resolves this vulnerability.
Fixed in 25.4R1-S3-EVO
Upgrade
Upgrade Juniper Junos OS Evolved to a version that resolves this vulnerability.
Fixed in 25.4R2-EVO
Upgrade
Upgrade Juniper Junos OS Evolved to a version that resolves this vulnerability.
Fixed in 25.4X300-D40-EVO
Upgrade
Upgrade Juniper Junos OS Evolved to a version that resolves this vulnerability.
Fixed in 26.2R1-S2-EVO
Upgrade
Upgrade Juniper Junos OS Evolved to a version that resolves this vulnerability.
Fixed in 26.2R2-EVO
Upgrade
Upgrade Juniper Junos OS Evolved to a version that resolves this vulnerability.
Fixed in 26.4R1-EVO
Upgrade
Upgrade Juniper Junos OS to a version that resolves this vulnerability.
Fixed in 23.2R2-S7.7
Upgrade
Upgrade Juniper Junos OS to a version that resolves this vulnerability.
Fixed in 23.4R2-S8.13
Upgrade
Upgrade Juniper Junos OS to a version that resolves this vulnerability.
Fixed in 24.2R2-S5.5
Upgrade
Upgrade Juniper Junos OS to a version that resolves this vulnerability.
Fixed in 24.4R2-S5
Upgrade
Upgrade Juniper Junos OS to a version that resolves this vulnerability.
Fixed in 25.2R2-S2
Upgrade
Upgrade Juniper Junos OS to a version that resolves this vulnerability.
Fixed in 25.4R1-S3
Upgrade
Upgrade Juniper Junos OS to a version that resolves this vulnerability.
Fixed in 25.4R2
Upgrade
Upgrade Juniper Junos OS to a version that resolves this vulnerability.
Fixed in 26.2R1-S2
Upgrade
Upgrade Juniper Junos OS to a version that resolves this vulnerability.
Fixed in 26.2R2
Upgrade
Upgrade Juniper Junos OS to a version that resolves this vulnerability.
Fixed in 26.4R1

Event History

Oct 14, 2026

CVE Published

via MITRE·04:53 PM

Data Sourced

via MITRE·04:53 PM

RemedyDescriptionSeverityWeakness

Frequently Asked Questions

Which systems and interfaces are exposed?

Systems running Juniper Networks Junos OS or Junos OS Evolved are exposed where Unified Access Policy is enabled on an interface that can receive LLDP traffic from an adjacent attacker.

Does exploitation require credentials or user interaction?

No. The attacker is adjacent to the affected interface and does not need authentication or user interaction; exploitation is performed through LLDP traffic.

What is the potential impact of successful exploitation?

An attacker may crash the l2cpd process, causing denial of service, or execute arbitrary code with root privileges.