CVE Vulnerabilities


Exposure of Resource to Wrong Sphere

Published: Jan 12, 2024 | Modified: Jan 19, 2024
CVSS 3.x
CVSS 2.x

An Exposure of Resource to Wrong Sphere vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on MX Series allows an unauthenticated, network-based attacker to bypass the intended access restrictions.

In an Abstracted Fabric (AF) scenario if routing-instances (RI) are configured, specific valid traffic destined to the device can bypass the configured lo0 firewall filters as its received in the wrong RI context.

This issue affects Juniper Networks Junos OS on MX Series:

  • All versions earlier than 20.4R3-S9;
  • 21.2 versions earlier than 21.2R3-S3;
  • 21.4 versions earlier than 21.4R3-S5;
  • 22.1 versions earlier than 22.1R3;
  • 22.2 versions earlier than 22.2R3;
  • 22.3 versions earlier than 22.3R2.


The product exposes a resource to the wrong control sphere, providing unintended actors with inappropriate access to the resource.

Affected Software

Name Vendor Start Version End Version
Junos Juniper 20.4 (including) 20.4 (including)
Junos Juniper 20.4-r1 (including) 20.4-r1 (including)
Junos Juniper 20.4-r1-s1 (including) 20.4-r1-s1 (including)
Junos Juniper 20.4-r2 (including) 20.4-r2 (including)
Junos Juniper 20.4-r2-s1 (including) 20.4-r2-s1 (including)
Junos Juniper 20.4-r2-s2 (including) 20.4-r2-s2 (including)
Junos Juniper 20.4-r3 (including) 20.4-r3 (including)
Junos Juniper 20.4-r3-s1 (including) 20.4-r3-s1 (including)
Junos Juniper 20.4-r3-s2 (including) 20.4-r3-s2 (including)
Junos Juniper 20.4-r3-s3 (including) 20.4-r3-s3 (including)
Junos Juniper 20.4-r3-s4 (including) 20.4-r3-s4 (including)
Junos Juniper 20.4-r3-s5 (including) 20.4-r3-s5 (including)
Junos Juniper 20.4-r3-s6 (including) 20.4-r3-s6 (including)
Junos Juniper 20.4-r3-s7 (including) 20.4-r3-s7 (including)
Junos Juniper 20.4-r3-s8 (including) 20.4-r3-s8 (including)

Extended Description

Resources such as files and directories may be inadvertently exposed through mechanisms such as insecure permissions, or when a program accidentally operates on the wrong object. For example, a program may intend that private files can only be provided to a specific user. This effectively defines a control sphere that is intended to prevent attackers from accessing these private files. If the file permissions are insecure, then parties other than the user will be able to access those files. A separate control sphere might effectively require that the user can only access the private files, but not any other files on the system. If the program does not ensure that the user is only requesting private files, then the user might be able to access other files on the system. In either case, the end result is that a resource has been exposed to the wrong party.