CVE-2024-23684 is a vulnerability classified under CWE-407 (Inefficient Algorithmic Complexity) found in the DecodeFromBytes function of the com.upokecenter.cbor Java library, which implements the Concise Binary Object Representation (CBOR) standard. Versions 4.0.0 through 4.5.1 are affected. The flaw arises because the decoding algorithm can be forced into a computationally expensive state by specially crafted input data, causing excessive resource consumption and leading to denial of service (DoS). This vulnerability can be exploited remotely without requiring authentication or user interaction, making it a significant risk for applications that parse CBOR data from untrusted sources. The attack vector involves sending malicious CBOR-encoded payloads that trigger the inefficient decoding path, potentially exhausting CPU or memory resources. While no public exploits have been reported yet, the high CVSS score of 7.5 reflects the ease of exploitation and the impact on availability. The vulnerability does not affect confidentiality or integrity, but the service disruption can affect dependent systems and users. The lack of an official patch at the time of reporting means organizations must implement interim mitigations. Given the widespread use of CBOR in IoT, mobile, and web services, this vulnerability could have broad implications depending on deployment context.

For European organizations, the primary impact is denial of service, which can disrupt critical services, degrade user experience, and cause operational downtime. Sectors such as telecommunications, finance, healthcare, and public administration that utilize Java applications parsing CBOR data are particularly vulnerable. Disruptions could affect real-time data processing, IoT device management, and inter-service communications that rely on CBOR encoding. The remote exploitation capability increases risk exposure, especially for internet-facing services. Additionally, denial of service incidents can lead to reputational damage and potential regulatory scrutiny under frameworks like GDPR if service availability impacts user rights or contractual obligations. The absence of confidentiality or integrity compromise limits data breach risks, but availability impacts alone can have significant operational and financial consequences.

Immediate mitigation steps include implementing strict input validation and sanitization to detect and reject malformed or suspicious CBOR payloads before decoding. Rate limiting and connection throttling can reduce the risk of resource exhaustion from repeated malicious requests. Monitoring application performance and resource usage can help detect early signs of exploitation attempts. Organizations should isolate vulnerable components and apply network segmentation to limit exposure. Since no official patch is currently available, tracking vendor updates and applying patches promptly upon release is critical. Where feasible, consider using alternative CBOR libraries not affected by this vulnerability or updating to fixed versions once published. Conducting a thorough inventory of software dependencies to identify affected versions is essential for targeted remediation. Finally, incorporating this vulnerability into incident response and threat hunting activities will improve detection and response capabilities.