CVE-2024-3411: IPMI Authentication Bypass Vulnerability

CVE-2024-3411 Overview

CVE-2024-3411 is a critical vulnerability affecting implementations of IPMI (Intelligent Platform Management Interface) authenticated sessions. The vulnerability stems from insufficient randomness in session management, specifically in the generation of IPMI Session IDs and BMC (Baseboard Management Controller) Random Numbers. This weakness allows attackers to hijack active sessions or forge spoofed IPMI packets to gain unauthorized control over BMC devices.

The Intelligent Platform Management Interface is widely used in data center environments for out-of-band server management, making this vulnerability particularly concerning for enterprise infrastructure. Successful exploitation enables attackers to bypass security controls and manage BMC devices without proper authentication.

Critical Impact

Attackers can hijack IPMI sessions and gain unauthorized management access to BMC devices, potentially compromising entire server infrastructure through predictable session identifiers or weak random number generation.

Affected Products

• IPMI implementations with weak random number generation
• Dell iDRAC8 (prior to security update DSA-2024-295)
• BMC devices implementing IPMI 2.0 with insufficient session randomness

Discovery Timeline

• April 30, 2024 - CVE-2024-3411 published to NVD
• November 4, 2025 - Last updated in NVD database

Technical Details for CVE-2024-3411

Vulnerability Analysis

This vulnerability is classified under CWE-331 (Insufficient Entropy), which describes security issues arising from inadequate randomness in cryptographic or session management operations. The IPMI protocol requires strong random numbers for session establishment to prevent session prediction and hijacking attacks.

When an IPMI session is established, the BMC generates a Session ID and random number that are used as part of the authentication handshake. If these values are predictable or generated using a weak pseudo-random number generator (PRNG), an attacker who can observe network traffic may be able to predict future session identifiers or replay/forge IPMI packets.

The vulnerability allows network-based attacks without requiring prior authentication or user interaction. Successful exploitation can result in complete compromise of confidentiality and integrity of the affected BMC device, enabling unauthorized remote management operations.

Root Cause

The root cause is insufficient entropy in the random number generation process used during IPMI session establishment. Specifically, the vulnerability exists because:

1. Predictable Session IDs: The IPMI Session ID may be generated using a weak or predictable algorithm, allowing attackers to anticipate valid session identifiers
2. Weak BMC Random Numbers: The random numbers generated by the BMC during authentication may have insufficient entropy, making them susceptible to prediction or brute-force attacks
3. Protocol Design Weakness: The IPMI specification may not enforce strong randomness requirements, leading to varying implementation quality across vendors

Attack Vector

The attack can be executed remotely over the network without requiring authentication or user interaction. An attacker positioned on the same network segment as the target BMC can:

1. Passive Observation: Monitor IPMI traffic to collect session establishment data and identify patterns in session ID or random number generation
2. Session Prediction: Analyze collected data to predict future session identifiers or random numbers
3. Session Hijacking: Inject spoofed IPMI packets using predicted session credentials to take over an existing session
4. Unauthorized Access: Execute management commands on the BMC as if authenticated, potentially modifying system configuration, accessing sensitive data, or disrupting server operations

The attack does not require the attacker to have valid credentials or prior access to the system. The network-based nature of the attack vector means that any system with IPMI accessible over the network is potentially vulnerable.

Detection Methods for CVE-2024-3411

Indicators of Compromise

• Unusual IPMI session activity or unexpected management commands being executed on BMC devices
• Multiple IPMI sessions from unexpected source IP addresses
• Anomalous patterns in session establishment attempts indicating probing for predictable session IDs
• Unauthorized configuration changes to server hardware or BMC settings

Detection Strategies

• Monitor IPMI network traffic (UDP port 623) for anomalous patterns or unexpected session activity
• Implement network segmentation to isolate IPMI/BMC management traffic and enable focused monitoring
• Deploy intrusion detection systems (IDS) with signatures for IPMI session anomalies
• Review BMC audit logs for unauthorized access attempts or suspicious administrative actions

Monitoring Recommendations

• Establish baseline IPMI traffic patterns and alert on deviations
• Configure logging on BMC devices to capture all authentication and session events
• Implement SIEM correlation rules to detect multiple failed session attempts followed by successful access
• Monitor for IPMI traffic from unauthorized network segments or external sources

How to Mitigate CVE-2024-3411

Immediate Actions Required

• Apply vendor-specific security patches, such as Dell Security Update DSA-2024-295 for iDRAC8 devices
• Restrict IPMI/BMC network access to dedicated management VLANs with strict access controls
• Review the CERT Vulnerability Advisory VU#163057 for comprehensive guidance
• Disable IPMI over LAN if remote BMC management is not required

Patch Information

Dell has released security update DSA-2024-295 to address this vulnerability in iDRAC8 devices. Organizations should consult the Intel IPMI Specification Update Document for protocol-level guidance and contact their specific BMC vendor for firmware updates addressing the weak random number generation issue.

Administrators should prioritize patching BMC firmware and implement network controls while awaiting vendor patches for devices without available updates.

Workarounds

• Isolate IPMI/BMC management interfaces on a dedicated, physically or logically separate management network
• Implement strict firewall rules to limit IPMI access to authorized management workstations only
• Enable IPMI encryption where supported to add an additional layer of session protection
• Consider disabling IPMI over LAN entirely and using serial-over-LAN or physical console access as alternatives

# Configuration example - Restrict IPMI access via firewall (iptables)
# Block IPMI UDP port 623 from untrusted networks
iptables -A INPUT -p udp --dport 623 -s 10.0.0.0/8 -j DROP
iptables -A INPUT -p udp --dport 623 -s 192.168.0.0/16 -j DROP
# Allow only from management VLAN
iptables -A INPUT -p udp --dport 623 -s 172.16.100.0/24 -j ACCEPT
iptables -A INPUT -p udp --dport 623 -j DROP