CVE-2022-32615 describes a dangerous vulnerability in CCD (Common Communications Driver) that could let a local attacker escalate their user privileges to system-level without user interaction. The core problem is an “out-of-bounds write” caused by the use of uninitialized data in the code—this means malicious code can overwrite parts of memory it’s not supposed to touch, potentially leading to full system compromise. If you’re running affected systems and haven’t patched yet, you’re at serious risk.

* Severity: High
* Attack Type: Local (requires attacker to run code on the target device)
* User Interaction Needed: No
* System Privilege Needed: Yes (attacker's code needs to execute with system privileges for exploitation)
* Reference Fix: Patch ID: ALPS07326559; Issue ID: ALPS07326559

Background

The CCD component is used in many Android devices, often as part of the MediaTek platform. It manages communications between different system components. Like many system-level drivers, mistakes in CCD can have dire consequences.

This particular flaw allows the attacker—if they have the ability to execute code on the device—to potentially overwrite critical portions of system memory by exploiting uninitialized data within the CCD driver.

What is an Out-of-Bounds Write?

An out-of-bounds write happens when software writes data past the end of an allocated buffer or to an unexpected memory location. Uninitialized data compounds this risk; if the code doesn't set a variable to a known state before use, it might contain attacker-controlled data or random memory leftover, leading to unpredictable and often exploitable behavior.

Let's look at a simple, abstracted code example to get the idea

// Vulnerable code snippet
struct packet_info {
    int len;
    char data[256];
};

void handle_packet(struct packet_info *pkt) {
    char buffer[256];
    // Here, pkt->len may be uninitialized or controlled by attacker
    memcpy(buffer, pkt->data, pkt->len);
}

In this example

- If an attacker somehow gets pkt->len set to a value greater than 256, they will overwrite buffer, causing memory corruption.

In the real-world vulnerable binary, the uninitialized field and lack of bounds check means local code can manipulate the driver's handling of buffers to trigger an out-of-bounds write.

Requirements

- Attacker can execute code locally on the device (e.g., via a malicious app, or as a lower-privileged user)

Exploitation Flow

1. Prepare an Attack Vector: The attacker crafts a packet or system call to the driver that triggers the flawed code path with attacker-controlled data.
2. Trigger Uninitialized Use: The attacker arranges conditions so that the code does not initialize part of a structure or buffer. This could be by sending partial input, using intended (but buggy) interfaces, or abusing race conditions.
3. Overflow Critical Buffer: With the uninitialized (and attacker-controlled) size or pointer, the driver writes out-of-bounds, possibly overwriting control structures or function pointers.
4. Escalate Privileges: The attacker injects shellcode or alters the execution flow, gaining system or root privileges.

Real-Life Example (Pseudo-Exploit)

# Pseudo-python for PoC; real exploit would need native code with syscall or ioctl
import os

def trigger_ccd_vuln():
    # Open vulnerable device node
    fd = os.open("/dev/ccd", os.O_RDWR)
    # Create malicious input with size field set intentionally large
    payload = b"A" * 300  # input bigger than internal buffer
    # Send payload
    os.write(fd, payload)
    os.close(fd)

trigger_ccd_vuln()

Actual exploitation would require more detailed knowledge of the CCD driver's internals, but the basic idea is to prepare data that, when processed by the old CCD code, causes a buffer overflow.

If you are a developer or device vendor

- Apply the fix as per ALPS07326559
- Make sure you fully initialize all data structures before use and add bounds checking on all buffers.

If you are a user

- Update your Android device to the latest firmware. Check with your carrier or phone manufacturer for security bulletins related to “MediaTek” or “CCD driver”.

Official References

- CVE-2022-32615 NVD Entry
- Android Security Bulletin June 2022
- MediaTek Security Adviosry Page

Conclusion

CVE-2022-32615 is serious for Android devices running vulnerable CCD drivers because it can let a local attacker escalate to full system privileges with no user interaction. Even without public exploits (yet), public disclosure means threat actors can soon develop their own—you should apply updates right away to prevent compromise.


Patch ID: ALPS07326559  
Issue ID: ALPS07326559


*Stay safe. Always patch your devices and watch security bulletins for your components.*

Timeline

Published on: 11/08/2022 21:15:00 UTC
Last modified on: 11/10/2022 15:04:00 UTC