CVE-2023-28323: Ivanti EPM Privilege Escalation Flaw

CVE-2023-28323 Overview

CVE-2023-28323 is an insecure deserialization vulnerability affecting Ivanti Endpoint Manager (EPM) 2022 Su3 and all prior versions. This vulnerability allows an unauthenticated remote attacker to exploit deserialization of untrusted data to elevate privileges on the affected system. The flaw can be chained with other operating system vulnerabilities to achieve full privilege escalation or used as a pivot point for lateral movement to other network-connected machines.

Critical Impact

Unauthenticated attackers can exploit this deserialization flaw to gain elevated privileges, potentially leading to complete system compromise and lateral movement across enterprise networks.

Affected Products

• Ivanti Endpoint Manager 2022 Su3
• Ivanti Endpoint Manager 2022 Su2
• Ivanti Endpoint Manager 2022 Su1
• Ivanti Endpoint Manager 2022 (base release)
• All Ivanti Endpoint Manager versions prior to 2022

Discovery Timeline

• 2023-07-01 - CVE-2023-28323 published to NVD
• 2025-05-05 - Last updated in NVD database

Technical Details for CVE-2023-28323

Vulnerability Analysis

This vulnerability falls under CWE-502 (Deserialization of Untrusted Data), a common class of security flaws that occurs when an application deserializes data from untrusted sources without proper validation. In the context of Ivanti Endpoint Manager, the application processes serialized objects from network requests without adequately verifying the integrity or origin of the data.

The attack requires no authentication or user interaction, and can be launched remotely over the network. When successfully exploited, an attacker gains full control over the confidentiality, integrity, and availability of the affected system. The vulnerability is particularly dangerous in enterprise environments where Ivanti EPM is used to manage endpoints across the organization, as compromising the management server could provide attackers with access to managed devices.

Root Cause

The root cause of CVE-2023-28323 lies in the improper handling of serialized data within Ivanti Endpoint Manager. The application fails to implement adequate validation and sanitization of serialized objects before deserializing them. This allows attackers to craft malicious serialized payloads that, when processed by the application, execute arbitrary code or manipulate application logic to elevate privileges.

Insecure deserialization vulnerabilities typically arise when developers trust serialized data without considering that an attacker may have tampered with it. In Java-based applications, this often involves exploiting gadget chains present in the application's classpath to achieve code execution during the deserialization process.

Attack Vector

The vulnerability is exploitable over the network by an unauthenticated attacker. The attack vector involves sending specially crafted serialized data to the vulnerable Ivanti EPM component. The exploitation process typically involves:

1. Identifying an endpoint that accepts serialized data
2. Crafting a malicious serialized payload using known gadget chains
3. Sending the payload to the target system
4. The deserialization process triggers the malicious code embedded in the payload
5. The attacker gains elevated privileges on the system

This exploit could be combined with other OS-level vulnerabilities to achieve full system compromise or used to pivot to other machines on the network.

Detection Methods for CVE-2023-28323

Indicators of Compromise

• Unexpected or anomalous network connections to the Ivanti EPM server from untrusted sources
• Unusual process spawning or child processes originating from Ivanti EPM services
• Suspicious serialized data patterns in network traffic targeting EPM endpoints
• Unexplained privilege escalation events on systems running Ivanti EPM

Detection Strategies

• Monitor network traffic for suspicious serialized object patterns targeting Ivanti EPM services
• Implement application-level logging to capture deserialization events and anomalies
• Deploy endpoint detection solutions capable of identifying exploitation attempts against deserialization vulnerabilities
• Use intrusion detection systems with signatures for known deserialization attack patterns

Monitoring Recommendations

• Enable verbose logging on Ivanti Endpoint Manager servers and forward logs to a SIEM solution
• Monitor for unusual authentication events or privilege changes on EPM servers
• Track network connections to and from EPM servers for anomalous behavior
• Implement file integrity monitoring on critical EPM application directories

How to Mitigate CVE-2023-28323

Immediate Actions Required

• Apply the security patch from Ivanti immediately as referenced in Ivanti Security Advisory SA-2023-06-20
• Restrict network access to Ivanti EPM servers to trusted IP ranges only
• Implement network segmentation to limit potential lateral movement if exploitation occurs
• Review server logs for any signs of prior exploitation attempts

Patch Information

Ivanti has released a security patch addressing this vulnerability. Organizations should refer to the Ivanti Security Advisory SA-2023-06-20 for detailed patching instructions and download links. It is critical to update all affected Ivanti Endpoint Manager installations to the latest patched version.

Workarounds

• Implement strict network access controls to limit exposure of Ivanti EPM services
• Deploy a web application firewall (WAF) capable of inspecting and blocking malicious serialized payloads
• Consider temporarily disabling non-essential external access to EPM servers until patching is complete
• Enable additional authentication requirements for accessing EPM administrative functions if available

# Network access restriction example for Linux-based firewall
# Restrict access to Ivanti EPM ports to trusted management networks only
iptables -A INPUT -p tcp --dport 443 -s 10.0.0.0/8 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP