Cilium is a networking, observability, and security solution with an eBPF-based dataplane. For users with the following configuration: 1. An allow policy that selects a Layer 3 destination and a port range `AND` 2. A Layer 7 allow policy that selects a specific port within the first policy's range the Layer 7 enforcement would not occur for the traffic selected by the Layer 7 policy. This issue only affects users who use Cilium's port range functionality, which was introduced in Cilium v1.16. This issue is patched in PR #35150. This issue affects Cilium v1.16 between v1.16.0 and v1.16.3 inclusive. This issue is patched in Cilium v1.16.4. Users are advised to upgrade. Users with network policies that match the pattern described above can work around the issue by rewriting any policies that use port ranges to individually specify the ports permitted for traffic.
This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 5.8, indicating it can be exploited remotely over the network with relatively low complexity without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts limited data confidentiality, for affected systems. Impacting 1 product from cilium organizations running these solutions should prioritize assessment and patching.
Reported in 2024, this vulnerability emerged during an era marked by increased sophistication in supply chain attacks, cloud infrastructure vulnerabilities, and software-as-a-service (SaaS) security challenges. Security practices during this period emphasized zero-trust architectures, container security, and API protection.
2024-11-25T19:15:11.373
2025-09-03T17:18:14.773
Analyzed
CVSSv3.1: 5.8 (MEDIUM)
SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For cilium's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.