CVE-2021-26987: VMware Spring Boot RCE Vulnerability

CVE-2021-26987 Overview

Element Plug-in for vCenter Server incorporates SpringBoot Framework. SpringBoot Framework versions prior to 1.3.2 are susceptible to a vulnerability which when successfully exploited could lead to Remote Code Execution. All versions of Element Plug-in for vCenter Server, Management Services versions prior to 2.17.56 and Management Node versions through 12.2 contain vulnerable versions of SpringBoot Framework.

Critical Impact

This Remote Code Execution vulnerability affects multiple NetApp products that incorporate vulnerable versions of SpringBoot Framework, potentially allowing unauthenticated attackers to execute arbitrary code on affected systems over the network.

Affected Products

• VMware Spring Boot (versions prior to 1.3.2)
• NetApp Element Plug-in for vCenter Server (all versions)
• NetApp Management Services for Element Software and NetApp HCI (versions prior to 2.17.56)
• NetApp SolidFire & HCI Management Node (versions through 12.2)

Discovery Timeline

• March 15, 2021 - CVE-2021-26987 published to NVD
• November 21, 2024 - Last updated in NVD database

Technical Details for CVE-2021-26987

Vulnerability Analysis

This vulnerability exists within the SpringBoot Framework incorporated into multiple NetApp products. The underlying issue allows attackers to achieve Remote Code Execution on vulnerable systems without requiring any authentication or user interaction. Due to the network-based attack vector, exploitation can be performed remotely against any exposed vulnerable service, making this particularly dangerous for internet-facing deployments.

The vulnerability is especially concerning because it affects a third-party library (SpringBoot Framework) that is embedded across multiple NetApp products. This creates a supply chain security concern where a single library vulnerability cascades to impact multiple enterprise products managing virtualization and storage infrastructure.

Root Cause

The root cause of this vulnerability stems from vulnerable versions of the SpringBoot Framework (versions prior to 1.3.2) that are incorporated into NetApp's Element Plug-in for vCenter Server and related management software. The specific vulnerable component within SpringBoot has not been publicly detailed, but the exploitation path allows for remote code execution without requiring privileges or user interaction.

Attack Vector

The attack vector is network-based, meaning an attacker can exploit this vulnerability remotely without any prerequisites such as valid credentials or user interaction. The vulnerability affects systems that have the vulnerable products accessible over the network. Given that these products typically manage virtualization infrastructure and storage systems, successful exploitation could provide attackers with significant access to critical enterprise infrastructure.

Successful exploitation would allow an attacker to execute arbitrary code in the context of the affected application, potentially leading to complete system compromise, data exfiltration, or lateral movement within the target environment.

Detection Methods for CVE-2021-26987

Indicators of Compromise

• Unexpected processes spawned by the Element Plug-in for vCenter Server service
• Anomalous network connections originating from management services to external IP addresses
• Unauthorized modifications to system files or configurations on affected management nodes
• Unusual authentication events or privilege escalation attempts on vCenter infrastructure

Detection Strategies

• Monitor for suspicious Java process activity associated with SpringBoot-based applications on affected systems
• Implement network traffic analysis to detect unusual outbound connections from vCenter management components
• Review application logs for error messages or exceptions indicative of exploitation attempts
• Deploy endpoint detection capabilities on systems running affected NetApp software

Monitoring Recommendations

• Enable verbose logging for Element Plug-in for vCenter Server and Management Services
• Configure alerting for process creation events associated with vCenter plugin services
• Monitor network traffic for command-and-control patterns from management nodes
• Implement file integrity monitoring on critical system directories

How to Mitigate CVE-2021-26987

Immediate Actions Required

• Upgrade NetApp Management Services to version 2.17.56 or later
• Update NetApp SolidFire & HCI Management Node beyond version 12.2
• Apply vendor-provided patches for Element Plug-in for vCenter Server
• Restrict network access to affected management interfaces until patches are applied
• Review systems for signs of compromise before and after patching

Patch Information

NetApp has released security updates to address this vulnerability. Refer to the NetApp Security Advisory for detailed patch information and upgrade instructions. Organizations should upgrade Management Services to version 2.17.56 or later and ensure Management Node versions are updated beyond 12.2.

Workarounds

• Implement network segmentation to restrict access to vulnerable management services
• Use firewall rules to limit network connectivity to affected systems from trusted sources only
• Consider disabling affected plugins until patches can be applied in environments where the risk is acceptable
• Deploy intrusion prevention systems with signatures for SpringBoot exploitation attempts

# Configuration example - Restrict network access to management services
# Example iptables rules to limit access to management ports
iptables -A INPUT -p tcp --dport 443 -s trusted_network/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP

# Verify current version of Management Services
# Check NetApp documentation for version verification commands