CVE-2023-4233 in oFono
Summary
by MITRE • 04/18/2024
A flaw was found in ofono, an Open Source Telephony on Linux. A stack overflow bug is triggered within the sms_decode_address_field() function during the SMS PDU decoding. It is assumed that the attack scenario is accessible from a compromised modem, a malicious base station, or just SMS.
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Analysis
by VulDB Data Team • 08/07/2025
The vulnerability identified as CVE-2023-4233 represents a critical stack overflow condition within the ofono telephony stack implementation on Linux systems. This flaw specifically manifests within the sms_decode_address_field() function during the processing of SMS Protocol Data Units, creating a potential pathway for arbitrary code execution or system instability. The ofono framework serves as a foundational component for telephony services in Linux environments, making this vulnerability particularly concerning for embedded systems and mobile device platforms that rely on this telephony stack for communication functionality. The vulnerability stems from insufficient input validation and boundary checking during the parsing of SMS PDU address fields, where maliciously crafted SMS messages can trigger buffer overflow conditions that corrupt the program's stack memory.
The technical exploitation of this vulnerability follows a well-established pattern that aligns with CWE-121, which addresses stack-based buffer overflow conditions. The attack vector can be initiated through three primary scenarios as outlined in the vulnerability description, each representing a different threat model that demonstrates the breadth of potential attack surfaces. When a compromised modem is used, attackers can leverage the modem's direct access to telecommunications infrastructure to inject malicious SMS content that triggers the overflow. Similarly, a malicious base station scenario allows attackers to intercept and modify SMS traffic at the wireless network level, while the third vector indicates that even standard SMS transmission can serve as an attack vector. This multi-vector approach makes the vulnerability particularly dangerous as it can be exploited through various network positions and attack models, ranging from sophisticated targeted attacks to more opportunistic exploitation.
The operational impact of CVE-2023-4233 extends beyond simple system crashes or denial of service conditions. The stack overflow condition can potentially lead to complete system compromise when executed successfully, as attackers may be able to manipulate the program execution flow to redirect control to malicious code. This vulnerability particularly affects Linux systems implementing ofono for telephony services, including but not limited to mobile devices, embedded communication systems, and IoT devices that rely on telephony functionality. The implications are severe for any system where SMS communication is enabled, as the vulnerability can be triggered without requiring physical access to the device, making it a significant concern for both enterprise and consumer environments. The attack scenario is particularly concerning from an ATT&CK framework perspective as it relates to T1059.007 for execution through SMS-based attacks and T1566 for initial access through malicious telecommunications content.
Mitigation strategies for CVE-2023-4233 must address both immediate defensive measures and long-term architectural improvements. The most effective immediate response involves applying patches from the ofono project maintainers or updating to versions that contain fixed implementations of the sms_decode_address_field() function with proper input validation and boundary checking. Organizations should implement network monitoring to detect anomalous SMS traffic patterns that might indicate exploitation attempts, particularly focusing on SMS messages with malformed address fields. System administrators should consider disabling SMS functionality on systems where it is not essential, reducing the attack surface for potential exploitation. Additionally, implementing proper input sanitization and validation mechanisms within telephony applications can provide additional defense in depth. From a security architecture standpoint, the vulnerability highlights the importance of applying principle of least privilege to telephony services and implementing network segmentation to limit the potential impact of successful exploitation. The vulnerability also emphasizes the need for regular security assessments of telephony stacks and the implementation of robust memory safety practices within telecommunications software development processes.