CVE-2022-3510 is a denial of service (DoS) vulnerability affecting multiple versions of Google's Protocol Buffers (protobuf-java core and lite) prior to versions 3.21.7, 3.20.3, 3.19.6, and 3.16.3. The vulnerability arises from a parsing issue related to Message-Type Extensions. Specifically, when inputs contain multiple instances of non-repeated embedded messages that include repeated or unknown fields, the protobuf library converts objects repeatedly between mutable and immutable forms. This back-and-forth conversion leads to excessive memory allocation and deallocation, causing prolonged garbage collection (GC) pauses. These GC pauses can degrade application performance significantly or cause the application to become unresponsive, effectively resulting in a denial of service condition. The issue is similar in nature to CVE-2022-3171 but targets protobuf-java core and lite versions. The vulnerability is categorized under CWE-400 (Uncontrolled Resource Consumption), indicating that it exploits inefficient resource management to disrupt service availability. No known exploits have been reported in the wild to date. The recommended remediation is to upgrade protobuf-java to the fixed versions 3.21.7, 3.20.3, 3.19.6, or 3.16.3 or later. Since protobuf is widely used for data serialization in many Java-based applications and services, this vulnerability could impact any system that processes untrusted or malformed protobuf messages using the affected versions.

For European organizations, the impact of CVE-2022-3510 primarily concerns service availability. Applications and services that rely on vulnerable protobuf-java versions for message serialization and deserialization could experience significant performance degradation or outages if targeted with crafted protobuf messages exploiting this parsing flaw. This is especially critical for high-availability systems such as financial transaction platforms, telecommunications infrastructure, healthcare data systems, and cloud services that use protobuf for internal or external communication. The denial of service could disrupt business operations, cause downtime, and potentially lead to financial losses or reputational damage. Although the vulnerability does not directly compromise confidentiality or integrity, the resulting service disruption can indirectly affect operational continuity and trust. Since protobuf is embedded in many middleware, microservices, and API implementations, the scope of affected systems can be broad. European organizations with complex Java-based ecosystems or those using protobuf in critical infrastructure should be particularly vigilant. The absence of known exploits suggests that the threat is currently theoretical but the ease of triggering the issue through crafted inputs means attackers with network or input access could exploit it if unpatched.

1. Immediate upgrade of protobuf-java core and lite libraries to versions 3.21.7, 3.20.3, 3.19.6, or 3.16.3 or later is essential to eliminate the vulnerability. 2. Conduct an inventory of all applications and services using protobuf-java to identify vulnerable versions, including transitive dependencies in build systems like Maven or Gradle. 3. Implement input validation and filtering at network boundaries or application layers to detect and block malformed or suspicious protobuf messages that contain multiple instances of non-repeated embedded messages with repeated or unknown fields. 4. Monitor application performance and garbage collection metrics closely to detect unusual spikes or pauses that could indicate exploitation attempts. 5. Employ runtime protections such as resource limits or sandboxing for services processing untrusted protobuf data to mitigate impact if exploitation occurs. 6. Engage with software vendors and third-party providers to ensure their products are updated if they embed vulnerable protobuf versions. 7. For critical systems, consider deploying Web Application Firewalls (WAFs) or Intrusion Prevention Systems (IPS) with custom rules to detect protobuf message anomalies. 8. Maintain a robust patch management process to quickly apply updates for protobuf and related dependencies in the future.