CVE-2024-48984
CVE-2024-48984
Weakness (CWE)
CVSS Vector
v3.1- Attack Vector
- Network
- Attack Complexity
- Low
- Privileges Required
- None
- User Interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Description
An issue was discovered in MBed OS 6.16.0. When parsing hci reports, the hci parsing software dynamically determines the length of a list of reports by reading a byte from an input stream. It then fetches the length of the first report, uses it to calculate the beginning of the second report, etc. In doing this, it tracks the largest report so it can later allocate a buffer that fits every individual report (but only one at a time). It does not, however, validate that these addresses are all contained within the buffer passed to hciEvtProcessLeExtAdvReport. It is then possible, though unlikely, that the buffer designated to hold the reports is allocated in such a way that one of these out-of-bounds length fields is contained within the new buffer. When the (n-1)th report is copied, it overwrites the length field of the nth report. This now corrupted length field is then used for a memcpy into the new buffer, which may lead to a buffer overflow.
Comprehensive Technical Analysis of CVE-2024-48984
1. Vulnerability Assessment and Severity Evaluation
CVE ID: CVE-2024-48984 CVSS Score: 9.8
The vulnerability in MBed OS 6.16.0 involves a buffer overflow during the parsing of HCI (Host Controller Interface) reports. The issue arises from improper validation of addresses within the buffer passed to hciEvtProcessLeExtAdvReport. This can lead to out-of-bounds memory access, resulting in a buffer overflow.
Severity Evaluation:
- CVSS Base Score: 9.8 (Critical)
- Impact: High
- Exploitability: Medium to High
The high CVSS score indicates a critical vulnerability that could be exploited to cause significant damage, including arbitrary code execution, denial of service, or data corruption.
2. Potential Attack Vectors and Exploitation Methods
Attack Vectors:
- Network-Based Attacks: An attacker could send specially crafted HCI reports over the air to a vulnerable device, exploiting the buffer overflow.
- Local Exploitation: If an attacker has local access to the device, they could manipulate the input stream directly to trigger the vulnerability.
Exploitation Methods:
- Memory Corruption: By carefully crafting the input stream, an attacker could overwrite critical memory areas, leading to code execution or crashing the device.
- Denial of Service (DoS): Exploiting the buffer overflow could cause the device to crash, resulting in a DoS condition.
3. Affected Systems and Software Versions
Affected Software:
- MBed OS 6.16.0
Affected Systems:
- Devices running MBed OS 6.16.0, particularly those utilizing the BLE (Bluetooth Low Energy) stack.
4. Recommended Mitigation Strategies
Immediate Mitigation:
- Patching: Upgrade to a patched version of MBed OS that addresses this vulnerability.
- Input Validation: Implement additional input validation checks to ensure that all addresses are within the allocated buffer.
Long-Term Mitigation:
- Code Review: Conduct a thorough code review of the HCI parsing logic to identify and fix similar issues.
- Security Training: Ensure developers are trained in secure coding practices to prevent such vulnerabilities in the future.
5. Impact on Cybersecurity Landscape
Impact:
- IoT Devices: Given the widespread use of MBed OS in IoT devices, this vulnerability poses a significant risk to the security and stability of IoT ecosystems.
- Supply Chain: The vulnerability could affect the supply chain, as compromised devices could be used as entry points for further attacks.
- Regulatory Compliance: Organizations may face regulatory scrutiny if they fail to address this critical vulnerability promptly.
6. Technical Details for Security Professionals
Vulnerability Details:
- Root Cause: The vulnerability stems from the lack of validation for addresses within the buffer passed to
hciEvtProcessLeExtAdvReport. - Code Reference: The issue is located in the
hci_evt.cfile, specifically around line 1317.
Exploitation Steps:
- Craft Malicious Input: Create an input stream with carefully crafted HCI reports designed to trigger the buffer overflow.
- Send Input: Transmit the malicious input to the vulnerable device via BLE.
- Exploit Buffer Overflow: The device processes the input, leading to a buffer overflow and potential code execution or DoS.
Detection and Monitoring:
- Log Analysis: Monitor logs for unusual HCI report processing errors or crashes.
- Network Monitoring: Use network monitoring tools to detect anomalous BLE traffic that may indicate an exploitation attempt.
Conclusion: CVE-2024-48984 is a critical vulnerability in MBed OS 6.16.0 that requires immediate attention. Organizations should prioritize patching affected systems and implementing robust input validation to mitigate the risk. The potential impact on IoT devices and the broader cybersecurity landscape underscores the importance of addressing this vulnerability promptly.