CVE-2023-25775: Intel Ethernet RDMA Driver Escalation Flaw

CVE-2023-25775 Overview

CVE-2023-25775 is an improper access control vulnerability affecting the Intel(R) Ethernet Controller RDMA driver for Linux. The flaw exists in versions prior to 1.9.30 and allows an unauthenticated attacker to potentially escalate privileges via network access. This vulnerability represents a significant security risk for systems utilizing Intel Ethernet controllers with RDMA (Remote Direct Memory Access) functionality.

Critical Impact

Unauthenticated attackers can exploit this vulnerability remotely to gain elevated privileges on affected Linux systems, potentially leading to complete system compromise.

Affected Products

• Intel Ethernet Controller RDMA Driver for Linux versions prior to 1.9.30
• Linux systems utilizing Intel Ethernet controllers with RDMA capabilities
• NetApp products utilizing affected Intel drivers (see NetApp Security Advisory NTAP-20230915-0013)

Discovery Timeline

• August 11, 2023 - CVE-2023-25775 published to NVD
• November 21, 2024 - Last updated in NVD database

Technical Details for CVE-2023-25775

Vulnerability Analysis

This vulnerability stems from improper access control mechanisms within the Intel Ethernet Controller RDMA driver for Linux. RDMA technology allows direct memory access from one computer's memory to another without involving the operating system, which makes proper access control critical. When these controls are improperly implemented, attackers can bypass authentication requirements and gain unauthorized access to system resources.

The vulnerability enables remote exploitation without requiring any user interaction or prior authentication. An attacker with network access to a vulnerable system can potentially leverage this flaw to escalate their privileges, gaining unauthorized control over the affected system. The impact encompasses potential compromise of confidentiality, integrity, and availability of the system.

Root Cause

The root cause of CVE-2023-25775 is classified as CWE-284 (Improper Access Control). The Intel Ethernet Controller RDMA driver fails to properly validate or restrict access to certain functionality, allowing unauthenticated users to perform privileged operations. This type of vulnerability typically occurs when access control checks are missing, improperly implemented, or can be bypassed through specific input sequences or network requests.

Attack Vector

The attack vector for this vulnerability is network-based, requiring no authentication or user interaction. An attacker can exploit this vulnerability remotely by sending specially crafted network requests to systems running vulnerable versions of the Intel RDMA driver. The exploitation does not require local access or valid credentials, making it particularly dangerous for internet-facing systems or those accessible from untrusted network segments.

The vulnerability mechanism involves sending network requests that bypass the driver's access control mechanisms. When these requests are processed, the driver fails to properly validate the requester's authorization level, potentially granting elevated privileges to the unauthenticated attacker. For detailed technical information, refer to the Intel Security Advisory SA-00794.

Detection Methods for CVE-2023-25775

Indicators of Compromise

• Unexpected network traffic patterns targeting RDMA services on Intel Ethernet interfaces
• Unusual privilege escalation events or unauthorized administrative access on systems with Intel RDMA drivers
• Anomalous system behavior or process execution originating from network-triggered events
• Log entries indicating failed or successful unauthorized access attempts to RDMA-enabled resources

Detection Strategies

• Monitor network traffic for suspicious RDMA protocol communications, particularly from external or untrusted sources
• Implement host-based detection rules to identify privilege escalation attempts on systems with Intel RDMA drivers
• Deploy SentinelOne agents to detect and alert on anomalous process behavior and privilege changes
• Audit driver versions across the environment to identify systems running vulnerable versions prior to 1.9.30

Monitoring Recommendations

• Enable comprehensive logging for Intel Ethernet Controller RDMA driver activity
• Configure network monitoring to alert on unusual RDMA traffic volumes or connection patterns
• Implement endpoint detection and response (EDR) solutions to capture and analyze privilege escalation attempts
• Establish baseline network behavior for RDMA-enabled systems to detect deviations

How to Mitigate CVE-2023-25775

Immediate Actions Required

• Update the Intel Ethernet Controller RDMA driver to version 1.9.30 or later immediately
• Restrict network access to systems running RDMA services using firewall rules and network segmentation
• Review and audit systems with Intel Ethernet controllers to identify vulnerable driver versions
• Implement network monitoring to detect potential exploitation attempts while patching is in progress

Patch Information

Intel has released a security update addressing this vulnerability. Organizations should update the Intel Ethernet Controller RDMA driver for Linux to version 1.9.30 or later. The official security advisory is available at Intel Security Advisory SA-00794.

Additional patch information for specific distributions:

• Debian users should refer to Debian LTS Announcement #4 and Debian LTS Announcement #5
• NetApp customers should consult the NetApp Security Advisory NTAP-20230915-0013

Workarounds

• Implement strict network segmentation to isolate systems with RDMA-enabled Intel Ethernet controllers
• Disable RDMA functionality if not required for business operations until patching can be completed
• Apply firewall rules to restrict network access to RDMA services from trusted sources only
• Monitor affected systems closely for signs of exploitation until the patch is applied

# Check current Intel RDMA driver version
modinfo irdma | grep version

# Restrict network access to RDMA ports using iptables (example)
iptables -A INPUT -p tcp --dport 4791 -j DROP
iptables -A INPUT -p udp --dport 4791 -j DROP

# Disable RDMA module if not required (temporary mitigation)
modprobe -r irdma