Description
RIOT is a real-time multi-threading operating system that supports a range of devices that are typically 8-bit, 16-bit and 32-bit microcontrollers. The size check in the `gcoap_dns_server_proxy_get()` function contains a small typo that may lead to a buffer overflow in the subsequent `strcpy()`. In detail, the length of the `_uri` string is checked instead of the length of the `_proxy` string. The `_gcoap_forward_proxy_copy_options()` function does not implement an explicit size check before copying data to the `cep->req_etag` buffer that is `COAP_ETAG_LENGTH_MAX` bytes long. If an attacker can craft input so that `optlen` becomes larger than `COAP_ETAG_LENGTH_MAX`, they can cause a buffer overflow. If the input above is attacker-controlled and crosses a security boundary, the impact of the buffer overflow vulnerabilities could range from denial of service to arbitrary code execution. This issue has yet to be patched. Users are advised to add manual bounds checking.
EPSS Score:
1%
Comprehensive Technical Analysis of EUVD-2024-29855
1. Vulnerability Assessment and Severity Evaluation
The vulnerability described in EUVD-2024-29855 affects the RIOT operating system, specifically within the gcoap_dns_server_proxy_get() and _gcoap_forward_proxy_copy_options() functions. The issue arises from a typo in the size check and the lack of an explicit size check, respectively, leading to potential buffer overflows. The severity of this vulnerability is rated with a CVSS Base Score of 9.8, indicating a critical risk. The CVSS vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H highlights the following:
- Attack Vector (AV:N): Network-based attack.
- Attack Complexity (AC:L): Low complexity required for exploitation.
- Privileges Required (PR:N): No privileges are required.
- User Interaction (UI:N): No user interaction is required.
- Scope (S:U): Unchanged.
- Confidentiality (C:H): High impact on confidentiality.
- Integrity (I:H): High impact on integrity.
- Availability (A:H): High impact on availability.
2. Potential Attack Vectors and Exploitation Methods
The primary attack vectors for this vulnerability include:
- Network-based Attacks: An attacker can exploit this vulnerability by sending crafted network packets to the affected system. The lack of proper size checks in the
gcoap_dns_server_proxy_get()and_gcoap_forward_proxy_copy_options()functions allows for buffer overflows. - Denial of Service (DoS): By causing a buffer overflow, an attacker can crash the system, leading to a denial of service.
- Arbitrary Code Execution: If the buffer overflow is carefully crafted, it could lead to arbitrary code execution, allowing the attacker to take control of the affected device.
3. Affected Systems and Software Versions
The vulnerability affects RIOT OS versions up to and including 2023.10. Any device running this version of RIOT OS is potentially at risk. This includes a wide range of IoT devices and microcontrollers that rely on RIOT OS for their real-time operating system needs.
4. Recommended Mitigation Strategies
To mitigate the risk associated with this vulnerability, the following strategies are recommended:
- Patch Management: Apply the official patch once it becomes available. As of the latest update, the issue has yet to be patched, so users should monitor for updates from the RIOT OS project.
- Manual Bounds Checking: Implement manual bounds checking in the affected functions to prevent buffer overflows. This can be done by ensuring that the length of the
_proxystring is checked correctly and that theoptlenis validated againstCOAP_ETAG_LENGTH_MAX. - Network Segmentation: Isolate affected devices from critical networks to limit the potential impact of an exploit.
- Intrusion Detection Systems (IDS): Deploy IDS to monitor for unusual network traffic that may indicate an attempt to exploit this vulnerability.
- Regular Audits: Conduct regular security audits and code reviews to identify and address similar vulnerabilities.
5. Impact on European Cybersecurity Landscape
The impact of this vulnerability on the European cybersecurity landscape is significant due to the widespread use of RIOT OS in IoT devices. The potential for denial of service and arbitrary code execution poses a substantial risk to the integrity, confidentiality, and availability of affected systems. This vulnerability underscores the importance of robust security practices in the development and deployment of IoT devices, particularly in critical infrastructure and industrial control systems.
6. Technical Details for Security Professionals
Vulnerable Functions:
gcoap_dns_server_proxy_get(): The size check for the_uristring is incorrectly applied to the_proxystring, leading to a buffer overflow._gcoap_forward_proxy_copy_options(): Lacks an explicit size check before copying data to thecep->req_etagbuffer, which isCOAP_ETAG_LENGTH_MAXbytes long.
Code References:
Additional References:
Aliases:
- CVE-2024-32017
- GSD-2024-32017
Assigner:
- GitHub_M
EPSS Score:
- 1 (indicating a low likelihood of exploitation in the wild, but this should not be a reason to ignore the vulnerability)
ENISA IDs:
- Product: RIOT OS ≤ 2023.10
- Vendor: RIOT-OS
By addressing this vulnerability promptly and thoroughly, organizations can significantly reduce the risk of exploitation and ensure the security and reliability of their IoT deployments.