CVE-2024-8450: Planet GS-4210-24P2S Auth Bypass Flaw

CVE-2024-8450 Overview

CVE-2024-8450 is a critical hardcoded credentials vulnerability affecting certain PLANET Technology switch models. The vulnerability exists in the SNMPv1 service implementation, where a hard-coded community string allows unauthorized remote attackers to access the SNMP service with read-write privileges. This flaw enables complete network device compromise, including configuration manipulation, credential theft, and potential lateral movement across network infrastructure.

Critical Impact

Unauthorized remote attackers can leverage the hard-coded SNMP community string to gain full read-write access to affected switches, enabling complete device takeover, configuration changes, and network reconnaissance without authentication.

Affected Products

• PLANET GS-4210-24P2S (Hardware Version 3.0) with vulnerable firmware
• PLANET GS-4210-24PL4C (Hardware Version 2.0) with vulnerable firmware
• PLANET GS-4210-24P2S Firmware (all versions prior to patch)
• PLANET GS-4210-24PL4C Firmware (all versions prior to patch)

Discovery Timeline

• September 30, 2024 - CVE-2024-8450 published to NVD
• October 4, 2024 - Last updated in NVD database

Technical Details for CVE-2024-8450

Vulnerability Analysis

This vulnerability stems from the use of hardcoded credentials (CWE-798) within the SNMPv1 service implementation on PLANET Technology managed switches. The affected devices contain a static, hard-coded community string that cannot be changed by administrators. SNMPv1 relies on community strings as the sole authentication mechanism, and when these strings are predictable or hard-coded, any attacker who discovers the string gains complete access to the device's SNMP interface.

The network-accessible nature of SNMP services (typically UDP port 161) combined with the lack of authentication requirements means attackers can remotely enumerate and exploit vulnerable devices without prior access or user interaction. With read-write privileges, an attacker can modify device configurations, extract sensitive network information, disable security features, or pivot to other network segments.

Root Cause

The root cause of CVE-2024-8450 is the inclusion of a static, hard-coded SNMP community string within the firmware of affected PLANET Technology switches. This represents a fundamental violation of secure development practices, as credentials should never be embedded in firmware or source code. The hard-coded string persists across device reboots and firmware updates, making it impossible for administrators to remediate without a vendor-provided patch.

Attack Vector

The attack vector for this vulnerability is network-based and requires no authentication or user interaction. An attacker can exploit this vulnerability by:

1. Identifying PLANET Technology switches on the target network through port scanning (UDP 161)
2. Using SNMP enumeration tools with the known hard-coded community string
3. Accessing the SNMPv1 service with full read-write privileges
4. Extracting device configurations, VLAN information, and network topology data
5. Modifying switch configurations to facilitate further attacks or persistence

The vulnerability is particularly dangerous in environments where switches are accessible from untrusted network segments or where network segmentation is insufficient.

Detection Methods for CVE-2024-8450

Indicators of Compromise

• Unexpected SNMP traffic (UDP port 161) to PLANET Technology switches from unknown sources
• Configuration changes on affected switches without corresponding administrator activity
• SNMP GET/SET requests using the hard-coded community string in network traffic captures
• Unauthorized modifications to VLAN configurations, port settings, or access control lists
• Anomalous network reconnaissance activity originating from switch management interfaces

Detection Strategies

• Deploy network intrusion detection systems (IDS) with signatures for unauthorized SNMP access attempts
• Monitor SNMP traffic patterns to affected device models for unusual community string usage
• Implement network flow analysis to detect reconnaissance activities targeting UDP port 161
• Configure SIEM rules to alert on SNMP configuration changes during non-maintenance windows
• Conduct regular audits of switch configurations to identify unauthorized modifications

Monitoring Recommendations

• Enable logging on all network switches and forward logs to a centralized SIEM platform
• Monitor for SNMP authentication failures and successful connections from unexpected IP addresses
• Implement network segmentation to isolate management interfaces from general network traffic
• Deploy honeypots configured to mimic PLANET Technology switches to detect active exploitation attempts
• Regularly review access logs for the management network segment containing affected devices

How to Mitigate CVE-2024-8450

Immediate Actions Required

• Disable SNMPv1 on all affected PLANET Technology switches if not operationally required
• Implement strict access control lists (ACLs) to restrict SNMP access to authorized management hosts only
• Isolate affected switches on a dedicated management VLAN with limited network access
• Monitor network traffic for exploitation attempts targeting UDP port 161 on affected devices
• Contact PLANET Technology support for firmware update availability and remediation guidance

Patch Information

Organizations should consult the official security advisories from TW-CERT for the latest patch information. The TW-CERT Security Advisory and TW-CERT Security Notification provide authoritative guidance on remediation steps and firmware updates from PLANET Technology.

Workarounds

• Disable SNMPv1 entirely and migrate to SNMPv3 with strong authentication if supported by the device firmware
• Configure firewall rules to block UDP port 161 traffic from untrusted network segments
• Implement network access control (NAC) to prevent unauthorized devices from communicating with switch management interfaces
• Deploy out-of-band management networks to completely isolate switch administration from production traffic
• Use VPN tunnels for any remote management access to affected network infrastructure

# Example: ACL configuration to restrict SNMP access (device-specific syntax may vary)
# Restrict SNMP access to authorized management hosts only
access-list 10 permit 192.168.1.100  # Management workstation
access-list 10 permit 192.168.1.101  # SNMP monitoring server
access-list 10 deny any log

# Apply ACL to SNMP service
snmp-server community <string> RO 10