CVE-2023-54330: Inbit Messenger Buffer Overflow Flaw

CVE-2023-54330 Overview

CVE-2023-54330 is a critical remote stack-based buffer overflow vulnerability affecting Inbit Messenger versions 4.6.0 through 4.9.0. The vulnerability allows unauthenticated attackers to execute arbitrary code by sending specially crafted malformed network packets to the messenger's network handler. Successful exploitation enables attackers to overwrite the Structured Exception Handler (SEH) and execute shellcode on vulnerable Windows systems, potentially leading to complete system compromise.

Critical Impact

Unauthenticated remote code execution via network-based attack requiring no user interaction. Attackers can achieve complete control of affected Windows systems running vulnerable Inbit Messenger versions.

Affected Products

• Inbit Messenger version 4.6.0
• Inbit Messenger version 4.7.0 through 4.8.x
• Inbit Messenger version 4.9.0

Discovery Timeline

• 2026-01-13 - CVE-2023-54330 published to NVD
• 2026-01-13 - Last updated in NVD database

Technical Details for CVE-2023-54330

Vulnerability Analysis

This vulnerability is classified as CWE-121 (Stack-based Buffer Overflow), a memory corruption flaw that occurs when data is written beyond the boundaries of a fixed-length stack buffer. In the case of Inbit Messenger, the network handler component fails to properly validate the length of incoming network packets before copying them into a stack-allocated buffer.

The vulnerability is particularly severe because it can be exploited remotely over the network without requiring authentication or user interaction. The attack targets the messenger's network processing functionality, which listens for incoming connections and handles message data. When a malformed packet with excessive data is received, the buffer overflow corrupts adjacent stack memory, including the Structured Exception Handler (SEH) chain.

SEH-based exploits are a well-documented technique on Windows systems where attackers overwrite exception handler pointers to redirect execution flow. By carefully crafting the overflow payload, an attacker can control the SEH pointer and ultimately execute arbitrary shellcode with the privileges of the Inbit Messenger process.

Root Cause

The root cause of CVE-2023-54330 is improper input validation in the network packet handler. The vulnerable code copies incoming network data to a fixed-size stack buffer without verifying that the data length does not exceed the buffer's capacity. This lack of bounds checking allows attackers to provide oversized input that overwrites critical stack structures, including saved return addresses and exception handler records.

Attack Vector

The attack is network-based, requiring the attacker to send specially crafted packets to a system running a vulnerable version of Inbit Messenger. The attack flow involves:

1. Identifying a target system running Inbit Messenger 4.6.0 through 4.9.0
2. Crafting a malicious network packet containing a payload designed to overflow the stack buffer
3. Sending the packet to the target, triggering the buffer overflow
4. Overwriting the SEH chain with attacker-controlled addresses
5. Executing shellcode that provides the attacker with remote access or other malicious capabilities

The vulnerability mechanism involves crafting oversized network packets that overflow the stack buffer in Inbit Messenger's network handler. The overflow corrupts the SEH chain, allowing attackers to redirect program execution to attacker-controlled shellcode. For detailed technical analysis and proof-of-concept information, refer to the GitHub Exploit Writeup and Exploit-DB #51126.

Detection Methods for CVE-2023-54330

Indicators of Compromise

• Unusual network traffic patterns targeting Inbit Messenger ports with large or malformed packets
• Crash dumps or application faults in Inbit Messenger processes indicating memory corruption
• Unexpected child processes spawned by the Inbit Messenger executable
• Evidence of shellcode execution or suspicious command-line activity associated with the messenger process
• Network connections from Inbit Messenger to known malicious command-and-control infrastructure

Detection Strategies

• Deploy network intrusion detection rules to identify oversized or malformed packets targeting Inbit Messenger
• Monitor for SEH exploitation indicators using endpoint detection and response (EDR) solutions
• Configure application crash monitoring to alert on repeated Inbit Messenger failures
• Implement deep packet inspection to detect exploitation payloads in network traffic

Monitoring Recommendations

• Enable process behavior monitoring on systems running Inbit Messenger to detect anomalous execution patterns
• Log all network connections to and from Inbit Messenger processes for forensic analysis
• Configure SentinelOne to monitor for memory corruption attack patterns and SEH exploitation techniques
• Establish baseline network behavior for Inbit Messenger to identify deviations indicative of attack attempts

How to Mitigate CVE-2023-54330

Immediate Actions Required

• Identify all systems running Inbit Messenger versions 4.6.0 through 4.9.0 in your environment
• Consider disabling or uninstalling Inbit Messenger until a patched version is available
• Implement network-level controls to restrict access to Inbit Messenger services from untrusted networks
• Deploy endpoint protection solutions capable of detecting and blocking buffer overflow exploits
• Monitor affected systems for signs of compromise using the indicators listed above

Patch Information

No vendor patch information is currently available in the CVE data. Organizations should consult the VulnCheck Security Advisory for the latest remediation guidance. Given the critical severity and unauthenticated remote code execution capability, affected organizations should prioritize mitigating this vulnerability through network controls or application removal until an official patch is released.

Workarounds

• Block network access to Inbit Messenger from untrusted networks using firewall rules
• Restrict Inbit Messenger to internal network segments with strict access controls
• Consider migrating to alternative messaging solutions that do not have known critical vulnerabilities
• Implement network segmentation to limit the blast radius if exploitation occurs

# Example: Block external access to Inbit Messenger (adjust port as needed)
# Windows Firewall rule to block inbound connections from external networks
netsh advfirewall firewall add rule name="Block Inbit Messenger External" dir=in action=block protocol=tcp localport=<MESSENGER_PORT> remoteip=any