CVE-2024-11580

Executive Summary

CVE-2024-11580 is a critical heap-based buffer overflow vulnerability in Luxion KeyShot, a professional 3D rendering and animation application. The flaw resides in the parsing of ABC (Alembic) files, a common interchange format for computer graphics. Successful exploitation requires user interaction—the victim must open a malicious ABC file or visit a malicious page that triggers the file parsing. An attacker can leverage this to execute arbitrary code in the context of the current user process, leading to full system compromise. The vulnerability has a CVSS score of 7.8 (High) and is currently unpatched, with no public exploit code or detection templates available. The EPSS score is 0.0%, indicating low exploitation likelihood in the wild, but the risk remains significant for targeted attacks.

CVSS Breakdown & Threat Level

• CVSS Score: 7.8 (High)
• Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
• Attack Vector: Local (requires opening a malicious file)
• Attack Complexity: Low
• Privileges Required: None
• User Interaction: Required (victim must open file)
• Scope: Unchanged
• Confidentiality Impact: High
• Integrity Impact: High
• Availability Impact: High

Threat Level: High. Although no active exploitation has been observed, the vulnerability allows remote code execution with minimal user interaction. The lack of a patch makes all installations of Luxion KeyShot vulnerable.

Deep Dive & Mechanics

The vulnerability is a classic heap-based buffer overflow (CWE-122) in the ABC file parsing routine of Luxion KeyShot. ABC (Alembic) files are used to store complex 3D scene data, including geometry, animations, and metadata. The specific flaw occurs when the parser reads a user-supplied length value from the file and uses it to copy data into a heap-allocated buffer without proper validation. By providing an overly large length value, an attacker can cause a buffer overflow, overwriting adjacent heap memory. This can corrupt critical data structures or function pointers, leading to arbitrary code execution.

Root Cause: Lack of bounds checking on the length of user-supplied data before memcpy or similar operation.

Attack Vector: The attacker crafts a malicious ABC file with a manipulated length field. When the victim opens the file in KeyShot, the parser reads the length, allocates a buffer based on the attacker-controlled value, and then copies data beyond the buffer's boundaries.

Impact: Code execution in the context of the current user. This can lead to data theft, installation of malware, or lateral movement within the network.

Vulnerable vs. Patched Code

Since no patch is available, a direct comparison is not possible. However, based on the vulnerability description, the vulnerable code likely resembles:

// Vulnerable pseudo-code
void parse_abc_data(char *input, size_t input_len) {
    size_t data_len = *(size_t*)input; // Attacker-controlled length
    char *buffer = malloc(data_len);   // Allocates based on attacker length
    memcpy(buffer, input + 8, data_len); // No validation, potential overflow
}

A patched version would include bounds checking:

// Patched pseudo-code
void parse_abc_data(char *input, size_t input_len) {
    size_t data_len = *(size_t*)input;
    if (data_len > input_len - 8) { // Validate against actual input size
        // Error handling
        return;
    }
    char *buffer = malloc(data_len);
    memcpy(buffer, input + 8, data_len);
}

Exploitation & Lab Setup

Red Team (Exploitation)

Prerequisites:

• Luxion KeyShot installed (any version)
• Ability to deliver a malicious ABC file to the target (e.g., via email, download)

Exploitation Steps:

1. Craft the Malicious ABC File: Use a hex editor or custom script to modify a valid ABC file. Overwrite the length field at a known offset with a large value (e.g., 0xFFFFFFFF) and place shellcode in the data section.
2. Deliver the File: Send the file via phishing email or host it on a malicious website.
3. Trigger the Vulnerability: The victim opens the file in KeyShot. The parser reads the oversized length, causing a heap overflow that overwrites a function pointer or return address.
4. Gain Code Execution: The shellcode executes, providing a reverse shell or other payload.

Example Payload (Conceptual):

# Python script to craft malicious ABC file
import struct

def craft_malicious_abc():
    # Valid ABC header
    header = b'\x41\x42\x43\x00'  # ABC magic
    # Attacker-controlled length (large value)
    length = 0xFFFFFFFF
    # Shellcode (placeholder)
    shellcode = b'\x90' * 1000  # NOP sled + actual shellcode
    # Craft the malicious data
    payload = header + struct.pack('<I', length) + shellcode
    with open('malicious.abc', 'wb') as f:
        f.write(payload)

craft_malicious_abc()

Blue Team (Defense & Detection)

Detection:

• Monitor for unusual file opens of ABC files, especially from untrusted sources.
• Use endpoint detection and response (EDR) to detect heap-based buffer overflow behavior (e.g., abnormal memory allocation, crashes).
• Deploy network monitoring for ABC file transfers (e.g., via email or web downloads).

Mitigation:

• Restrict execution of KeyShot to trusted users only.
• Use application whitelisting to prevent unauthorized software.
• Implement file reputation services to block malicious ABC files.
• Educate users about the risks of opening files from unknown sources.

Indicators of Compromise (IOCs)

• File Hashes (SHA256): (None available, but monitor for suspicious ABC files)
• Network Indicators: Outbound connections from KeyShot process to unknown IPs (potential reverse shell)
• Process Anomalies: KeyShot.exe spawning child processes (e.g., cmd.exe, powershell.exe)
• Registry/File System: Creation of new files in temporary directories or startup folders
• Memory Artifacts: Heap corruption, abnormal memory allocation patterns

Detection Engineering

YARA Rule

rule CVE_2024_11580_ABC_Overflow {
    meta:
        description = "Detects malicious ABC files exploiting CVE-2024-11580"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2024-11580"
    strings:
        $abc_magic = { 41 42 43 00 } // ABC file magic bytes
        $large_length = { FF FF FF FF } // Potential oversized length
    condition:
        $abc_magic at 0 and $large_length
}

Sigma Rule

title: Suspicious ABC File Open in Luxion KeyShot
id: 8a9b3c4d-5e6f-7a8b-9c0d-1e2f3a4b5c6d
status: experimental
description: Detects opening of ABC files in KeyShot, potentially exploiting CVE-2024-11580
author: Valters IT
date: 2025-04-10
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith: '\KeyShot.exe'
        CommandLine|contains: '.abc'
    condition: selection
falsepositives:
    - Legitimate use of ABC files
level: high

Suricata Rule

alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"CVE-2024-11580 Potential ABC File Transfer"; flow:to_server; content:"|41 42 43 00|"; depth:4; content:"|FF FF FF FF|"; within:100; classtype:attempted-user; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable ABC File Parsing: If possible, configure KeyShot to not open ABC files automatically.
2. User Education: Train users to avoid opening ABC files from untrusted sources.
3. Network Controls: Block ABC file attachments at email gateways and web proxies.

Long-Term Fix:

• Await an official patch from Luxion. Monitor vendor advisories for updates.
• Consider using alternative 3D file formats (e.g., OBJ, FBX) until a patch is available.

Workaround:

• Use a sandbox or virtualized environment to open ABC files.
• Implement application control policies to restrict KeyShot execution.

Valters IT