CVE-2026-104597 in libosmocore
Summary
by MITRE • 10/26/2026
libosmocore through 1.14.1 contains an out-of-bounds read in iuup_rx_initialization() in src/gsm/iuup.c. This allows a remote attacker to obtain sensitive information.
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Analysis
by VulDB Data Team • 10/26/2026
The vulnerability identified within libosmocore versions up to and including 1.14.1 represents a critical memory safety flaw located specifically within the iuup_rx_initialization function found in the src/gsm/iuup.c source file. This component is integral to the OpenBSC project, which implements base station controller functionality for GSM networks using the Inter-Office User Part protocol over IP. The core technical issue stems from an improper boundary check during the parsing or processing of incoming signaling messages. When the function processes specific input data structures, it fails to validate that the requested read operation remains within the allocated memory buffer limits. This lack of rigorous bounds checking allows the application to access memory addresses that lie beyond the intended end of a valid array or buffer structure.
From a technical perspective, this flaw is classified as an out-of-bounds read vulnerability, which aligns with Common Weakness Enumeration identifier CWE-125. In practical terms, when a remote attacker sends a specially crafted packet to the vulnerable service, the application attempts to dereference memory locations that are not part of the legitimate data payload. Because this operation is a read rather than a write, it does not directly allow for arbitrary code execution or system compromise through buffer overflow techniques. Instead, the primary consequence is information disclosure. The attacker can potentially extract sensitive internal state information, such as stack contents, heap metadata, or other private variables residing in adjacent memory regions that are exposed by this erroneous read operation.
The operational impact of this vulnerability is significant for telecommunications infrastructure providers relying on libosmocore for their GSM network operations. Since the flaw allows a remote attacker to obtain sensitive information without authentication, it poses a severe risk to confidentiality and potentially integrity if the leaked data can be correlated with other system behaviors. In the context of GSM networks, leaking internal state or memory contents could aid an adversary in further reconnaissance efforts, facilitating more sophisticated attacks such as protocol manipulation or denial-of-service conditions by understanding how the stack handles specific message sequences. This undermines the trust model inherent in cellular network signaling protocols where integrity and confidentiality are paramount for secure communication between base stations and core network elements.
Mitigation strategies must focus on both immediate remediation and long-term defensive coding practices. The most effective solution is to upgrade libosmocore to a version later than 1.14.1, where the developers have presumably implemented proper bounds checking within the iuup_rx_initialization function to ensure that all memory accesses remain strictly within allocated limits. For environments where immediate patching is not feasible due to operational constraints, network-level mitigations should be employed. This includes restricting access to the affected services via firewall rules or Access Control Lists to only trusted IP addresses associated with legitimate base station controllers and core network nodes. Additionally, deploying intrusion detection systems capable of identifying anomalous signaling patterns may help in detecting exploitation attempts before they result in successful data exfiltration.
From a broader security architecture standpoint, this vulnerability highlights the importance of rigorous input validation in protocol parsers used within critical infrastructure. It serves as a reminder that even read-only memory errors can lead to significant security breaches by exposing internal system details. Security teams should also consider implementing Address Sanitizers during development and testing phases to catch such out-of-bounds accesses early in the software lifecycle. Furthermore, adhering to secure coding standards like those outlined in CWE-20 for proper input validation is essential to prevent similar flaws across other components of the telecommunications stack. By addressing this issue through both patching and architectural hardening, organizations can significantly reduce their attack surface against remote information disclosure threats targeting GSM signaling protocols.