CVE-2024-27130 - Buffer Copy Vulnerability in QNAP Operating Systems: Exploit Details and Solutions

Recently, researchers have discovered a vulnerability listed as CVE-2024-27130 in several QNAP operating system versions. This vulnerability is a buffer copy without checking the size of input and, if exploited, can allow a user to execute arbitrary code through a network. In this post, we will be discussing the details of the exploit, affected versions, and proper precautions to take.

Exploit Details

The exploit takes advantage of a failure to check the input size when copying data to a buffer. By sending a crafted packet with an oversized payload, an attacker can overrun the buffer and cause code execution. We can demonstrate this with a simple code snippet:

def vulnerable_function(input_data):
    buffer = bytearray(1024)
    input_size = len(input_data)
    # Missing check for input_size <= 1024
    for i in range(input_size):
        buffer[i] = input_data[i]
    # ... rest of the code

By sending an input_data larger than the buffer size (1024 in this case), the attacker can overwrite parts of memory meant to be protected. This part of memory may hold critical data, program flow, or even allow remote code execution.

This vulnerability has been officially announced and documented in the following links

- CVE Details
- QNAP Security Advisory

QuTS hero h5.1.7.277 build 20240520 and later

It is highly recommended that affected users update their systems to one of the fixed versions immediately, to prevent potential exploits.

Patch Details

The vulnerability was fixed by adding a proper check for the size of the input in question before performing the buffer copy operation:

def fixed_function(input_data):
    buffer = bytearray(1024)
    input_size = len(input_data)
    if input_size > 1024:
        raise ValueError('Input data too large')
    for i in range(input_size):
        buffer[i] = input_data[i]
    # ... rest of the code

Conclusion

In summary, the CVE-2024-27130 vulnerability in QNAP operating systems is a highly critical issue that could potentially lead to remote code execution. To secure your systems, ensure that you have updated to the latest fixed versions of QTS or QuTS hero as mentioned above. Please refer to the original references for further details and stay vigilant against possible exploits.

Timeline

Published on: 05/21/2024 16:15:25 UTC
Last modified on: 06/04/2024 17:46:20 UTC