CVE-2024-30384 in Junos OS
Summary
by MITRE • 04/12/2024
An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on EX4300 Series allows a locally authenticated attacker with low privileges to cause a Denial-of-Service (Dos).
If a specific CLI command is issued, a PFE crash will occur. This will cause traffic forwarding to be interrupted until the system self-recovers.
This issue affects Junos OS:
All versions before 20.4R3-S10,
21.2 versions before 21.2R3-S7,
21.4 versions before 21.4R3-S6.
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Analysis
by VulDB Data Team • 02/07/2025
The vulnerability identified as CVE-2024-30384 represents a critical weakness in the Packet Forwarding Engine implementation of Juniper Networks Junos OS running on EX4300 Series devices. This flaw manifests as an improper check for unusual or exceptional conditions within the PFE component, creating a pathway for locally authenticated attackers to trigger system instability. The vulnerability specifically targets the command-line interface functionality where certain commands can induce a crash state in the forwarding engine, fundamentally disrupting network operations and creating a denial-of-service condition that affects the entire device's ability to process and forward network traffic.
The technical exploitation of this vulnerability occurs through the execution of a specific CLI command that causes the PFE to enter an unrecoverable crash state. This condition results in complete interruption of traffic forwarding capabilities, forcing the system to rely on automatic recovery mechanisms that may take considerable time to restore normal operations. The PFE crash represents a fundamental failure in the system's error handling and validation mechanisms, where the software does not properly validate input parameters or command sequences before executing potentially destructive operations. This type of vulnerability falls under the CWE-707 category of Improper Check for Unusual or Exceptional Conditions, which specifically addresses situations where software fails to properly detect and handle exceptional circumstances that could lead to system instability or compromise.
From an operational impact perspective, this vulnerability presents a significant risk to network availability and reliability, particularly in environments where continuous network connectivity is critical. The denial-of-service condition affects not just individual device functionality but can potentially cascade through network infrastructure, especially in scenarios where EX4300 series devices serve as core forwarding elements in larger network topologies. The attack vector requires local authentication, meaning that only users with legitimate access credentials can exploit this vulnerability, but this limitation does not diminish the potential impact on network operations and service availability. Network administrators must consider the implications of this vulnerability in their overall security posture, particularly given that it affects multiple version ranges of Junos OS, including several maintenance releases that may still be in active deployment.
The remediation strategy for this vulnerability requires immediate implementation of the vendor-supplied software patches and updates for the affected Junos OS versions. Organizations should prioritize upgrading their EX4300 Series devices to versions that include the necessary fixes, particularly focusing on the specified release versions that address this particular flaw. System administrators should also implement monitoring procedures to detect potential exploitation attempts and establish incident response protocols that account for the possibility of PFE crashes and subsequent recovery periods. The vulnerability demonstrates the importance of maintaining current software versions and implementing proper access controls to limit potential exploitation vectors, as the attack requires local authentication credentials. Additionally, network segmentation strategies and redundant path configurations should be considered to minimize the impact of such service interruptions on critical network services and applications that depend on continuous network connectivity.